When you have limited size profile or limited user permission on Terminal Server.

Even if Autoupdate is running user will be unable to install it and will get stuck in some temporary folder.

To disable Adobe autoupdate you have 2 oprions.

First is:Go to c:Program FilesCommon FilesAdobeUpdaterX (where X can be a number depending on you Adobe version)
Rename the following files Adobe_Updater.exe and AdobeUpdaterInstallMgr.exe

Second is:By deploying the following registry file via GPO

Windows Registry Editor Version 5.00[HKEY_CURRENT_USERSoftwareAdobeAcrobat Reader9.0Updater]
"bShowAutoUpdateConfDialog"=dword:00000000
"bShowNotifDialog"=dword:00000000
"iUpdateFrequency"=dword:00000000

Change the [HKEY_CURRENT_USERSoftwareAdobeAcrobat Reader7.0Updater according to your Acrobat version