Couldn't load XPCOM

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1

Howdy,

 This error (Couldn't load XPCOM.) started showing up 2 days ago. It pops up when trying to open
Mozilla Firefox, the browser will not open at all. Finding that this error was related to Web TuneUp I came here for help.  I'm running Win7pro x64, after searching system throughly for XPCOM I find reference to this JScript Script file "xpcomApi.js" twice (2 times).
  One is found at C:\ProgramData\AVG Web TuneUp\FireFoxExt\4.1.8.599\components
  The second location is C:\Users\All Users\AVG Web TuneUp\FireFoxExt\4.1.8.599\components.

  In both locations they have these 2 files sharing the same folder.  "toolbarhomeApi.js".
and "avg-dnt-policy.js".

  This trouble really makes me mad, with Firefox not able to open it becomes harder to export any settings to back up files. Copying all of the various mozzila directories should suffice to be able to restore Firefox later. If there is not a quick fix on this problem. I'm going to sit as is at the moment before any restore attempts or program removal or re-installs.
 
   Last year AVG-IS (2012) wiped out this whole computer after doing an auto-update of virus
definitions. Something corrupt in the definition file caused just about every file in Win7
to corrupt itself. I went insane…
 
  Thanks anyone,
       royblue

8

AVG,
   First off I owe you an apology, the fault seems to be with Firefox. I looked on the mozilla website. The
problem seems to occur when Firefox gets updates and they become corrupted leaving me with the (Couldn't load XPCOM.) error.
  I manually installed the latest Firefox version update over my existing Firefox. It's as it was before
this problem started. IE was working the whole period.
   Thanks,
       Roy

7

Hello Roy,
We understand how something like this can really try your patience. In this case, we request you to uninstall AVG Webtuneup from your pc and check whether firefox works fine in your pc.
Please feel free to contact us for any further assistance. Thank you.

5

AVG,
   First off I owe you an apology, the fault seems to be with Firefox. I looked on the mozilla website. The
problem seems to occur when Firefox gets updates and they become corrupted leaving me with the (Couldn't load XPCOM.) error.
  I manually installed the latest Firefox version update over my existing Firefox. It's as it was before
this problem started. IE was working the whole period.
   Thanks,
       Roy

4

Hello Roy,
Pleased to know your issue have been fixed. We appreciate your valuable effort in fixing the issue.
Please feel free to contact us for any further assistance. Thank you.

6

Hello Roy,
We are sorry for the difficulties you are currently experiencing. Are you able to open Internet Explorer, if so we request you to uninstall Mozilla Firefox from your pc and then reinstall it back in your pc and check whether it works.
Please feel free to contact us for any further assistance. Thank you.

3

AVG,
   Tried as you suggested, uninstalling AVG Webtuneup made no difference. Still get the same error (Couldn't load XPCOM.). Anymore ideas?

Thanks,
   roy

2

Hello Roy,
We understand how something like this can really try your patience. In this case, we request you to uninstall AVG Webtuneup from your pc and check whether firefox works fine in your pc.
Please feel free to contact us for any further assistance. Thank you.