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Installed v7 and Windows closes Firefox when loading with a DEP error

  • 1 reply
  • 75 have this problem
  • 4 views
  • Last reply by ZorMonkey

rbitzel
rbitzel
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I am running Firefox on an HP Compaq Presario F756NR laptop running Windows Vista Home Premium Service Pack 2. Firefox was working fine until I installed version 7. After 7 finished installing and I attempted to run Firefox Windows automatically closed Firefox and reported the following:

"Firefox has stopped working A problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available."

Once closed Windows returned the message: "Firefox was closed To help protect your computer, Data Execution Prevention has closed Firefox. Click to learn more."

Clicking the link provided this additional detail:

"Data Execution Prevention (DEP) is a security feature that can help prevent damage to your computer from viruses and other security threats. Harmful programs can try to attack Windows by attempting to run (also known as execute) code from system memory locations reserved for Windows and other authorized programs. These types of attacks can harm your programs and files.

DEP can help protect your computer by monitoring your programs to make sure that they use system memory safely. If DEP notices a program on your computer using memory incorrectly, it closes the program and notifies you."

I then attempted to change the Data Execution Prevention settings to allow Firefox to run but Windows would not allow me to change the settings and provided a message stating "This program must run with data execution protection (DEP) enabled. You cannot turn off DEP for this program."

I am running Firefox on an HP Compaq Presario F756NR laptop running Windows Vista Home Premium Service Pack 2. Firefox was working fine until I installed version 7. After 7 finished installing and I attempted to run Firefox Windows automatically closed Firefox and reported the following: "Firefox has stopped working A problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available." Once closed Windows returned the message: "Firefox was closed To help protect your computer, Data Execution Prevention has closed Firefox. Click to learn more." Clicking the link provided this additional detail: "Data Execution Prevention (DEP) is a security feature that can help prevent damage to your computer from viruses and other security threats. Harmful programs can try to attack Windows by attempting to run (also known as execute) code from system memory locations reserved for Windows and other authorized programs. These types of attacks can harm your programs and files. DEP can help protect your computer by monitoring your programs to make sure that they use system memory safely. If DEP notices a program on your computer using memory incorrectly, it closes the program and notifies you." I then attempted to change the Data Execution Prevention settings to allow Firefox to run but Windows would not allow me to change the settings and provided a message stating "This program must run with data execution protection (DEP) enabled. You cannot turn off DEP for this program."

All Replies (1)

ZorMonkey
ZorMonkey
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I had this problem, and found it was due to a trojan. Look for a file named javastat.dll on your system. For me it was in C:\Users\<User name>\AppData\Local\Temp . If you find it, try renaming/deleting it. You may have to boot into safe mode before Windows will let you, since the file may be in use. I used a virus scanner (I picked housecall.trendmicro.com) to clean it up, which detected it and cleaned it up just fine. After that, no more DEP errors!