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Firefox works, but Nightly error: XPCOM couldnt load

  • 15 tontu
  • 11 am na jafe-jafe bii
  • 19 views
  • i mujjee tontu mooy shadyz

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So today i've been having a lot of issues and trying to fix them ,i've found myself with this one

Firefox itself works fine, i even updated it, and am still able to write from it

But firefox Nightly cannot open , gives me that error: couldnt load XPCOM

Maybe iobit uninstaller deleted some registries that it needed? Or i removed some msconfig items at startup that it needed? Either way i didnt touch nightly itself , only windows explorer context menu with shellview type programs

Other than reinstalling, what could be the issue?

So today i've been having a lot of issues and trying to fix them ,i've found myself with this one Firefox itself works fine, i even updated it, and am still able to write from it But firefox Nightly cannot open , gives me that error: couldnt load XPCOM Maybe iobit uninstaller deleted some registries that it needed? Or i removed some msconfig items at startup that it needed? Either way i didnt touch nightly itself , only windows explorer context menu with shellview type programs Other than reinstalling, what could be the issue?

Saafara biñ tànn

I don't know what files Advanced SystemCare is protecting, but your Firefox profile folder isn't stored in the Firefox program folder, but is stored in a hidden location in AppData\Roaming and won't be affected by a reinstall.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\
Jàng tontu lii ci fi mu bokk 👍 3

All Replies (15)

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Activation context generation failed for "C:\Program Files (x86)\IVONA\IVONA Reader\IVONA Reader.exe". Dependent Assembly Microsoft.VC80.MFC,processorArchitecture="x86",publicKeyToken="1fc8b3b9a1e18e3b",type="win32",version="8.0.50727.6195" could not be found. Please use sxstrace.exe for detailed diagnosis.

This was a reoccuring error i kept getting I think ending the process tree of windows explorer at the time of getting this error (and i think while being in nightly) couldve started this new problem potentially

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https://support.mozilla.org/en-US/questions/943596

Thought this was related but then i don't really have a startup folder full of nightly.exe ? If anyone worthy can add to this so it makes (any) sense.

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Correction: It's the Developer edition

https://www.mozilla.org/en-US/firefox/developer/all/
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It's also supposedly synced up to firefox, but i'm not sure, when i logged in firefox it said last lync was march 2, which is obviously false, i have definitively at least once synced it up in this past month.

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where does firefox dev keep last sessions?

shadyz moo ko soppali ci

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An error message about XPCOM missing or about platform version usually happens because of a failed Firefox update that left you with a mixture of old and updated files in the Firefox program folder. This can happen in case security software was keeping a handle of some of the files in the Firefox program folder preventing Firefox from replacing all the files. You need to do a clean reinstall to ensure that all files are replaced. You may have to disable security software temporarily in case the problem persists.

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if i uninstall it from remove programs and install it again, is the profile going to be a-okay?

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also, yes that does seem plausible behavior from iobit advanced system care

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Saafara yiñ Tànn

I don't know what files Advanced SystemCare is protecting, but your Firefox profile folder isn't stored in the Firefox program folder, but is stored in a hidden location in AppData\Roaming and won't be affected by a reinstall.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\
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why do you think only firefox developer edition is having issues with xpcom ,isnt it the same xpcom that both are using i know i was having issues with the second drive on which dev edition is written, could that be it?

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where is xpcom located at? and if that ^ is the problem ,could a reinstall of the installation files fix this?

or maybe a change in properties/ownership

shadyz moo ko soppali ci

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I think this might end up being my issue with dll files

http://www.techsupportforum.com/forums/f217/the-file-c-windows-system32-msvcrt-dll-could-not-be-opened-478045.html

http://www.askvg.com/guide-how-to-restore-trustedinstaller-as-default-owner-of-a-file-or-folder-in-windows/

trustedinstaller is on the msvcrt-dll ,not sure about the other .dll files i kept getting errors for

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Any reason why the dev edition installation would be 1.6gb ?

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Solved: reinstalling dev edition fixed this xpcom problem in this case.