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"Error after installing new or updated antivirus software: Page fault in module ac1st15.dll
Published date: 2002-11-06
ID: TS73413
Applies to:
AutoCAD® 2002
AutoCAD® 2000i
AutoCAD LT® 2002
AutoCAD LT® 2000i
AutoSketch® 8
Issue
You installed Norton AntiVirus™ 2003 (NAV), Norton AntiVirus 2003 Professional Edition (NAV Pro) or Kaspersky™ 4.0.8 Anti-Virus software. Now, when you try to start an Autodesk® program, the following error message is displayed and the program does not start:

Page fault in module ac1st15.dll

Solution
There is a conflict between the functions of some antivirus software programs and the ac1st15.dll file.
To resolve this issue, download the updated ac1st15.dll file, and replace the file of the same name in the Autodesk product installation folder."

виж тук - http://usa.autodesk.com/adsk/servlet/ps/item?siteID=123112&id=2893426&linkID=2475323
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