Deleting Files

About file deletion

On most systems (including Windows and Mac) when you delete a file, that file is not actually deleted. What happens is that the computer will remove all links and references to it. With this done, you cannot see the file or search for it because the computer no longer knows where to find it.

The space that the file occupies is now declared as empty space and at some point another file will start to use that space and the original deleted file will be gone.

Until the space occupied by the original deleted file has been used a few times, it is possible to recover some or all of the original file using specialist software.

Simple Delete

A Simple Delete will either drop your file into the Recycle Bin or will appear to delete the file from your device (bearing in mind the information above). This is fine for getting rid of clutter or old files that you no longer want. You can then go and empty the Recycle Bin and continue to use your device as normal.

The types of files you might want to Simple Delete include:

• Downloaded files
• Application/software installation files
• Old documents or old drafts of work
• Images, audio or videos that you no longer need

Secure Delete

A Secure Delete will completely remove the files from your device. Securely deleted files should not be recoverable, even with specialist software. On most devices you will need to use specialist software to permanently remove files and we offer some suggestions in the Secure Delete sections below.

The types of files you may need to Secure Delete include:

• Notes from placements, especially if they could be used to identify a location or person
• Video and audio recordings with clients or "practice" patients
• Any data or information that you don't own i.e. data sourced as part of an assignment or study
• Personal files or images that you don't want anyone to have access to i.e. bank statements, scan of your passport, any private content

 

Simple delete files/folders

To do a simple delete of files on a Windows computer could not be much easier.

Click on a file or folder and hit the Delete key on your keyboard. Depending on your settings, you may be prompted to confirm you want to delete the item, at which point you click Yes. This item is now placed in the Recycle Bin. If you deleted something by mistake, you can simply go into the Recycle Bin and select to Restore the file(s) - no harm done.

Bypass the Recycle Bin

If you select a file and press Shift+Delete on your keyboard, the selected file(s) will bypass the Recycle Bin and will disappear. You cannot recover the file(s) from the Recycle Bin, because they are not there. Specialist software can recover these files.

Remember

Using Simple Delete techniques will not fully delete your files. To permanently remove files and folders from your Windows PC, you should see the Windows - Secure Delete section below.

Some files and folders won't delete

On all devices there are some files and folders that are designated as System Resources and deleting these will compromise or break your device. Because of this, a large number of files are protected and you will not be able to delete them.

Do not delete software - uninstall it

Unless you know what you are doing, do not try to delete software from your computer by any other method apart from using the built-in Apps & Features function. Using Windows Search find Apps & Features, select a piece of software from the list and select Uninstall. Follow the on screen prompts.

 

You can delete specific files or photos on Microsoft OneDrive, or you can delete entire folders and all the items in them. If you need to, you might be able to restore deleted files from the OneDrive recycle bin.

1. Go to the Student Hub and select OneDrive.

2. Select the files or folders you want to delete by pointing to each item and clicking the circle check box that appears. (The first image below shows items in List view, the second image shows items in Tiles or Photos view.)

 

3. To select all files in a folder, click the circle to the left of the header row, or press CTRL + A on your keyboard. (You can also select several files at once by selecting one file, scrolling down the list, then hold down the Shift key while left-clicking the last item you want to select.)

4. On the bar at the top of the page, select Delete. (You can also right-click the selected file or folder and select Delete.)

5. To delete a folder, rather than just its contents, you may need to go up or back a level to select the whole folder.

 

OneDrive and your own computer files

If you have linked your OneDrive to a folder on your computer, deleting the file from OneDrive will also delete that file from your computer. To stop this from happening you will need to move any files, that you want to keep on your computer, out of the OneDrive folder before you delete them online.

Text and images in this section are courtesy of Microsoft: Delete files or folders in OneDrive - Office Support (microsoft.com)

There are a few ways to do a Simple Delete on the Mac operating system, these are:

Drag to Trash

Simply click on an item or folder and drag it over the Trash icon in the Dock (that row of icons at the bottom of your screen).

Keyboard Delete Key

Select one or more items in Finder, or on your desktop, and hit the Delete key on your keyboard.

Finder Menu

When working in Finder, you can select one or more files and then click on the File menu button to select Move to Trash.

Right Click

Clicking on a file whilst simulating a right-click (press the Ctrl key on your keyboard when clicking on an item) will show you a context menu that includes the option to Move to Trash.

WARNING: All of the methods above will move your files into the Trash. These files can be recovered by simply opening up the Trash and dragging selected files back to either the Desktop or another location. They can also be recovered by right-clicking on files and selecting to Put Back which will return them to their original location.

If you select to Empty Trash then your files will no longer be discoverable, but may still be recoverable by specialist software.

 

Deleting Documents

To do a Simple Delete of documents on an iPhone or iPad, it is best that you open up the Files App:

Deleting a single item

1. Browse to the location of the file.

2. Press and hold an item to see the pop out context menu, then select Delete.

Selecting more than one item

To select more than one item for deletion, you will need to:

1. Browse to the location of the files.

2. Click on the Select button at the top of the screen.

3. Tick the checkbox that now appears next to all the items in that folder.

4. Click on Delete at the bottom of the screen.

Deleting a folder

You should be able to use either method (above) to delete a folder, but you may find that you have to delete everything within the folder first.

Some files and folders won't delete

On all devices there are some files and folders that are designated as System Resources and deleting these will compromise or break your device. Because of this, a large number of files are protected and you will not be able to delete them.

Deleting images, video and other media

A Simple Delete of images and media files will usually be completed through the Photos App and then following the process for deleting files: 

Deleting a single item

1. Browse to the location of the file.

2. Press and hold an item to see the pop out context menu, then select Delete.

Selecting more than one item

To select more than one item for deletion, you will need to:

1. Browse to the location of the files.

2. Click on the Select button at the top of the screen.

3. Tick the checkbox that now appears next to all the items in that folder.

4. Click on Delete at the bottom of the screen.

Recently Deleted

All documents, files, images and media deleted using the methods above are now in a Recently Deleted folder. Items can be easily recovered from here for up to 30 days after deletion.

iCloud Backup

REMEMBER: Many folders and files on an iPhone or iPad will automatically backup to iCloud and/or iTunes. You may need to delete copies of your deleted files from here too.

Deleting Apps

Do not attempt to locate App files for deletion as this may have negative consequences for your device. Always uninstall an App using the official method:

1. Touch and hold the App icon.

2. Tap on Remove App.

3. Tap Delete App and then tap Delete to confirm.

To complete a Simple Delete on an Android device, you will need to first locate the file(s).

Locating and deleting files on an Android device

All Android devices have a file manager already built in. Depending on the device manufacturer and the age of the device, these will have different names and icons. They may be called Files, File Manager, File Explorer or something else.

For the purposes of these instructions, I have installed the Files by Google app from the Play Store. This is a free app which works brilliantly at showing, sharing and managing the files on Android devices.

1. Open the Files by Google app, select Browse at the bottom of the screen and you will find that your files have already been categorised into:

Downloads
Images
Video
Audio
Documents
Apps

2. This should allow you to easily find files that you want to delete, but you can also use the Search function to directly discover a file if you know all or part of the file name.

3. Press and hold to select one or more items and a Delete button will appear at the foot of the screen. Hit delete to remove any selected file(s).

 

Note: Deleted files may still be recoverable unless your device is using encrypted storage. See Android - Secure Delete for more information.

Some files and folders won't delete

On all devices there are some files and folders that are designated as System Resources and deleting these will compromise or break your device. Because of this, a large number of files are protected and you will not be able to delete them. On an Android device, protected files are usually hidden from view and will require a change to device settings to make them visible. You should not attempt to do this unless you know what you are doing.

Where possible, you should not be using portable storage such as pendrives for storing, moving or sharing any files. You can use your university OneDrive for this purpose. See Cyber Security | Portable Media for more information.

Simple Delete from pendrives and other portable media

To complete a Simple Delete of items on a portable drive, you simply need to follow the instructions for your computer operating system.

Plug the portable drive into either your Windows computer or your Mac and then browse for items using the information provided on this page for Windows - Simple Delete or Mac - Simple Delete.

There are various ways to permanently delete files on a Windows computer and some are much more complicated than others. You may even have tools, through your anti-virus or security software that do this job for you. For the purposes of these instructions, we are going to use a well respected free 3rd party app called Eraser.

Download Eraser

The team over at PortableApps.com have made a portable version of Eraser available. This does not need a full traditional installation and will happily work from your desktop or a pendrive.

Go to the following link and click on the green Download from PortableApps.com button.

Eraser Portable (Secure erase utililty) | PortableApps.com

Enable EraserPortable

Once the download is complete (this should only take a moment as it is a very small file), locate and double click on the EraserPortable file:

This will trigger what looks like a Windows program installation, but it is only unpacking it and you will not need any special permissions to do this.

You will be asked to choose a location for the unpacking, click on Install and then a new EraserPortable folder will be created in the location you chose.

Run EraserPortable

Locate the EraserPortable folder and double click on EraserPortable.exe to run the program.

Select files/folders for permanent deletion using EraserPortable

With EraserPortable open you can add files for deletion using either of the following methods:

Drag and drop - Simply drag any files or folders, on your computer or a pendrive, into the EraserPortable window and they will be placed into a list pending permanent deletion.

Browse for files - This method takes a little more work, but you can click on the "Plus" symbol (top left):

Which will pop up the following window:

 

The options on this screen are Unused space which allows you to permanently delete all previous deleted files (this can take some time on larger drives), Files in folder which allows you to browse for whole folders on your computer and File which allows you to browse for individual files.

Whilst browsing, you can select folders/files - click Open in the browse window and then click OK in the EraserPortable popup window. Your selected folder/file will now be added to the deletion list.

Permanently delete your files

With your list of files ready, select them individually or click on Edit > Select all.

Some of the buttons in the top toolbar will change colour and allow you to perform actions:

 

Red X (Delete Task) - this means remove the task / cancel the deletion for this file. Any folders/files selected will be removed from the list and will not be deleted.

Green Play Button (Run) - this will begin the task of permanently deleting the selected folders/files. Clicking on this will present an additional warning to make sure you want to continue.

CAUTION!

A permanently deleted file, using EraserPortable is gone. You will not get that file back. Double check the list of files waiting for deletion and be sure they should all be there. The University of Cumbria, Eraser and PortableApps bear no responsibility if you delete the wrong files.

 

Having done a Simple Delete on files in your OneDrive, they drop into the OneDrive Recycle Bin from which you can restore them if you need to. To make sure these files are permanently deleted, you will need to follow these steps (Note: You need to complete ALL of the steps):

1. First, select Recycle bin in the OneDrive left hand side navigation.

2. Select specific files or folders from the recycle bin (just like you would in any other folder in OneDrive) then select Delete in the top navigation.

At this point, your files/folders should be gone but they are not. They are placed into a Second-stage recycle bin that holds them for 30 days in case you really didn't mean to delete them. To "finally" delete these deleted files you must now delete them again, but from this second stage area.

3. At the bottom of the Recycle Bin page, you will see a link to the Second-stage recycle bin. Click on this link to see what is in this second recycle bin, select files and delete again.

WARNING: Even now, your files are not completely and permanently deleted. There is a function in OneDrive that allows you to Restore your OneDrive. 30 days after deleting items from the Second-stage recycle bin, they will be gone forever.

 

Deleting files and folders on a Mac, simply places those items into the Trash and you can recover them by opening the Trash and dragging items back out.

If you empty the Trash, then your deleted files are no longer discoverable, but may still be recovered by using specialist software. This will be enough for most purposes and the deleted items will be overwritten by new files over time.

WARNING: If you have device sync enabled, you may also have copies of these files in your iCloud. Always check iCloud.com for copies and complete a Secure Delete here too. 

Permanent Secure Deletion

To ensure deleted files are totally and permanently removed, you will need to shred them using 3rd party eraser or shredding software.

Not many products in this category are free for Mac. Permanent Eraser by Edenwaith is not only free, but is well respected in this area.

1. Download and install Permanent Eraser from: Edenwaith : Products : Permanent eraser

2. With Permanent Eraser now available as an icon in your Dock, you can simply drag files onto the icon for permanent deletion

WARNING: Permanent Eraser will, by default, permanently delete your Trash whenever it is started. You will be warned it is going to do this and you will have the option to refuse/cancel.

Note: With macOS Catalina and later, Full Disk Access needs to be enabled to allow Permanent Eraser to erase the contents of the Trash.

After deleting files on an iPhone or iPad, these items are placed into the Recently Deleted area for 30 days. Your deleted files are easily recovered from Recently Deleted unless you delete them from here too.

Delete Recently Deleted

1. Open the Files app on your iPhone or iPad.

2. Reveal the sidebar in the app by tapping the Browse button.

3. Tap Recently Deleted from the sidebar.

4. Tap Select in the top right-hand corner.

5. Select Delete All at the bottom of the page.

6. Confirm that you wish to delete the files.

Because iPhones and iPads use encrypted storage, this should be enough to ensure that your files are gone and will not be recoverable and whilst specialist software may be able to access deleted files, it is very unlikely that they can be found.

WARNING: If you have device sync enabled, you may also have copies of these files in your iCloud. Always check iCloud.com for copies and complete a Secure Delete here too.

Once you have completed a Simple Delete of files/folders in your iCloud, they can still be recovered for up to 30 days after deletion. To speed up this process and ensure that the deleted files are gone forever, you will need to login to iCloud.com on the web (this process cannot be completed using the iCloud or iPhotos apps).

1. Login to icloud.com

2. Click on the Settings button

3. Scroll down to the bottom of the screen (under the "Advanced" heading) and select Restore Files

4. This will open up what is essentially a Recycle Bin and will be populated with your Recently Deleted items

5. If you have made a mistake deleting a file/folder, you can select them in this list and choose to Restore them

6. Select items in this list and click on Delete to permanently delete them

If your device is set up to use "encrypted storage", then a Simple Delete will usually be enough to permanently remove files. If you are in any doubt, then follow the instructions here for a Secure Delete.

Apps for Secure Delete

Some Android devices will already have a secure delete feature built into either the file management app or through security settings, but because all manufacturers handle this slightly differently (and some don't include it at all) I am going to use the free Shreddit Data Eraser App. There are many other similar apps available, both free and paid for, but always check the ratings and feedback before installing one.

Shreddit

1. Download and install Shreddit from the Play Store: Shreddit - Data Eraser - Apps on Google Play

2. Open the app and accept the request to access images, media and files - this is needed to allow files to be deleted.

3. At the top of the screen is a grey bar and image that says Internal Storage - you can click on this to start browsing for files to delete.

WARNING: On the Internal Storage bar is a three dots menu that gives the option to "Erase full storage". Do not select this unless you are intending to completely wipe your device prior to selling it. This option will permanently delete everything on your device.

4. When you have located the file(s) and/or folder(s) that you want to Secure Delete - tick the box next to their name

5. Hit the red floating Shreddit icon.

6. You will be prompted to confirm that this is the file/folder you want to delete.

WARNING: Once an item is deleted using Shreddit, it cannot be recovered. It is gone. Make sure you are only deleting things you want gone.

There are lots of additional settings available in Shreddit, including the strength of shredding, but the default settings are perfectly fine for most users.

Memory Cards

If you want to Secure Delete files from a memory card that is inserted into your Android device, Shreddit needs a whole new set of permissions and Android settings changes - it is best to remove the memory card and delete the files using a computer.

Where possible, you should not be using portable storage such as pendrives for storing, moving or sharing any files. You can use your university OneDrive for this purpose. See Cyber Security | Portable Media for more information.

Secure Delete from pendrives and other portable media

To complete a Secure Delete of items on a portable drive, you simply need to follow the instructions for your computer operating system.

Plug the portable drive into either your Windows computer or your Mac and then browse for items using the information provided on this page for Windows - Secure Delete or Mac - Secure Delete.