Occasionally you may need to deauthorise the Adobe Digital Editions (ADE) on your computer.

The main reasons for this tends to be if you have purchased a new computer, you need to deauthorise your old computer before you can authorise your new computer using the same Adobe ID. Or occasionally ADE can give an error, and the solution for it is to deauthorise and then reauthorise the software.

Please note that is you deauthorise a computer then you cannot open any ebooks that have Adobe DRM applied to them until you have reauthorised the computer again. Please also note that the computer must be authorised with the exact same Adobe ID. If you reauthorise with a different Adobe ID then the ebooks will not open, you will need to delete them and redownload them (but doing so will lose your notes and annotations).

To deauthorise, open Adobe Digital Editions. If you already have the software open and have an ebook open, please exit out of the ebook back to the library screen.

Then from the menu in the top left select Help > Erase Authorization (shortcut on Windows: Ctrl-Shift-D, on Mac: Cmd-Shift-D ). On the next screen you need to confirm by clicking "Erase Authorization". After you have done this deauthorisation is complete.

Occasionally ADE can have issues deauthorising and can present an error message. In these instances there is a way to manually erase the authorisation. The steps are different for PC and Mac, so please select the instructions that are correct for your computer.

For Windows:

1. Choose Start > Run.
2. In the Open text box, type regedit and then press Enter. The Registry Editor opens.
3. In the left pane of the Registry Editor, locate the following registry key:

HKEY_CURRENT_USER\Software\Adobe\Adept

4. Right-click the Adept key (folder) and choose Delete.
5. In the Confirm Key Delete dialog, click OK.

For Mac:

1. Open Adobe Digital Editions.
2. Press Cmd-Shift-D to deauthorize Adobe Digital Editions
3. Select Erase Authorization.
4. Click OK and quit Adobe Digital Editions.
5. Navigate to /Users/[[Your user account]]/Library/Application Support/Adobe/Digital Editions and drag the activation.dat file to the trash. ADE is now deauthorised.

If for some reason you cannot navigate to the activation.dat file (Mac OS X 10.7 and later), please try the following:

1. Go to the Finder menu.
2. Hold down the Option (Alt) key and select Go in the Finder menu bar. This reveals the hidden user Library below the current user's home directory.
3. Select Library.
4. Go to Application Support/Adobe/Digital Editions and delete the file named “activation.dat”

Next step

Now you've deauthorised ADE, if you need to reauthorise please follow our steps on Authorising Adobe Digital Editions (ADE) with an Adobe ID.

If you are still having difficulty deauthorising please contact our support team.