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"C:\Program Files\Mozilla Firefox.bak"


What is "C:\Program Files\Mozilla Firefox.bak" directory is used for? I tried to delete but it asks me for elevated privileges. Yes, it is a directory that has almost the exact size and contents.

Additional System Details

This happened

Not sure how often

This started when...

I am not sure. I've just browsed my PC and found this....

Installed Plug-ins

  • Shockwave Flash 11.4 r402
  • Yahoo Application State Plugin version
  • 5.1.10411.0
  • iTunes Detector Plug-in


  • User Agent: Mozilla/5.0 (Windows NT 6.1; rv:15.0) Gecko/20100101 Firefox/15.0

More Information

Windows 7, 32bit with SP1 including ALL MS updates (incl. NVidia network and video drivers updates)
Mozilla 15.

Nathan2055 11 solutions 110 answers

Are you the only user on this system or is there an administrator that preforms maintenance on your system?

Question owner

I am the only user that performs all the maintenance on my PC with Admin privileges.

osullic 0 solutions 2 answers

I too would like to know why this 'Mozilla Firefox.bak' directory has been created. I also am the sole user of my computer, and just discovered this directory. Is this a legitimate directory created by Firefox?

And I don't think the reply above should be marked as "chosen solution" when it clearly is nothing of the sort.

Ahmad Maher 0 solutions 7 answers

Me 3 !! , i found this folder in the program files and am the only user

could it be done by an add-on or something or it is by the Mozilla Maintenance Service ??

the main question : is it safe to delete it ??

i did run a scan on my system and there is no infection by virus or trojan or something like that so what made this folder ???

using FF 16.0.2 , Windows 7 sp1 ultimate x86