Adobe Reader 11.0.9 Error opening this document

Here’s a problem we encountered recently – if you update to Adobe Reader 11.0.9 and then get an error every time you double-click on a PDF file saying ‘Error opening this document’ you might want to know how to fix it.

In essence it seems that Adobe no longer trusts PDF documents on a network share, which could include My Documents and your Desktop. The fix is simple although a bit of a pain. This fix is stolen from and I can confirm it worked for us on the 1 PC we’ve had this on so far.

A. Fix One PC

  1. Launch Adobe Acrobat Reader X
  2. Go to: Edit > Preferences…
  3. Click on “General” in the left pane.
  4. Uncheck “Enable Protected Mode at startup”
  5. You will prompted with a dialog box to remind you to close the application for the change to go into effect. Click Yes.
  6. Click OK to save your change.
  7. Exit Adobe Reader

B. Fix Several PCs in Your Organization
Following the above steps aren’t practical if you have Adobe Acrobat installed on 1,000+ computers in 30 regional offices! Push this registry setting using your standard software deployment software.

[HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\10.0\Privileged]


Hopefully this will help you fix Adobe Reader 11.0.9 Error opening this document and similar error messages.