You can try to turn of protected mode.
I am still looking for an answer to this problem. I have noticed that if I double click on a pdf file in my email (outlook) i get the error message of access denied and if I then try to open a pdf that is stored on my desktop without closing and reopening the reader I get the same message. If I close reader and then manually start it, I can then open the files on my desktop but not on my email. Suggestions? I closed my security software to see if it was interfering but still have the same problem.
To make things simple for you, here are two ways for you fix the problem:
A. Fix One PC
- Launch Adobe Acrobat Reader X
- Go to: Edit > Preferences...
- Click on "General" in the left pane.
- Uncheck "Enable Protected Mode at startup"
- You will prompted with a dialog box to remind you to close the application for the change to go into effect. Click Yes.
- Click OK to save your change.
- 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.
Microsoft Outlook and other email clients
I hear this will also fix the "There was an error opening this document. Access denied." error that is occurring with any email client, including Microsoft Outlook Express; Microsoft Outlook 2010, 2007, 2003; Eudora; Mozilla Thunderbird.
Credit for this answer must go to http://www.brianstevenson.com/blog/adobe-acrobat-reader-x-there-was-error-opening-document -access-denied