well, why dont you take a few of your pdf files over to someone elses PC that has a known working edition of Acrobat (at or above your version # - which you didnt give - you should be using vers 7.0) and see if they open and close correctly. If they dont, you know its not your system, its corrupted files, or not created correctly.
and you ignored my point on checking to see how much free ram you have at time of closing pdf file by using freeware bysoft freeram, and havent said what your pagefile is set to.
also what you have after "noexecute=" in your boot.ini file in root directory of O/S
or perhaps this:
http://www.enfocus.com/download.php?id=855
http://www.planetpdf.com/
and you might also want to check your CPU usage
(Quote)
Support Knowledgebase
Freeze when you start Adobe Reader or Acrobat (6.0-7.x or 3D on Windows)
Issue
When you try to start Adobe Reader or Adobe Acrobat, the application immediately quits, appears to freeze, or returns the error "Can't find Acrobat Plug in."
Details
The process "acrobat.exe" uses 95% or more of the capacity of the system processor. (Acrobat 6.x)
The process "acrobat.exe" uses 25% or less of the capacity of the system processor. (Acrobat 7.x or 3D)
Acrobat 6.0 or Adobe Reader 6.0 was installed on the computer.
Solutions
Do one or more of the following solutions:
Solution 1: Delete the temporary files that Acrobat or Adobe Reader creates, and then install the update or upgrade.
Acrobat 6.0 and Adobe Reader 6.0 may not delete the temporary files that they create during normal processes, such as filling in forms. Because Acrobat and Adobe Reader check temporary files
at startup, an excess of temporary files can cause a long delay during startup or appear to be a freeze.
To delete temporary files:
1. Choose Start > Run, and type command in the Open text box. Click OK.
2. Type the following commands and press Enter after each command:
c:
cd\
del acr*.tmp /s
Note: Many lines of text will fill the Command.com window as this process runs. Wait for the process to complete (when the text has stopped for about 10 seconds), and then continue to the next step.
3. Type exit to close the Command.com window.
4. Install the 6.0.1 update, or upgrade to 7.0 or later.
Important: Before you upgrade to Acrobat 7.x or Adobe Reader 7.x1, remove Acrobat 6.x or Adobe Reader 6.x from your system. For instructions, see the Related Documents section of this document.
-- To install the Acrobat 6.0.1 update, download the update from the Adobe website at
www.adobe.com/support/downloads and then follow the online installation instructions.
-- To upgrade to Adobe Reader 7.x, remove Adobe Reader 6.0 from the computer, and then install Adobe Reader 7.x from the Adobe website at
www.adobe.com/products/acrobat/readstep2.html . For instructions on removing Adobe Reader 6, see Related Records.
-- To purchase Acrobat 7.x, visit the Adobe Store at
http://store.adobe.com/store/main.jhtml , or call Customer Services at 800- 833-6687 . Install Acrobat 7.x from your installation media and remove Acrobat 6.x when the installer prompts you.
-- If you have Acrobat 7 or Reader 7 already, download the latest updates from the Adobe website at
www.adobe.com/support/downloads and then follow the online installation instructions
etc.
http://www.adobe.com/support/techdocs/329444.html
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