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prefs can't be opened due to invalid character error code 800A03F6


Can't change prefs because the file can't be opened due to invalid character error code 800A03F6 User file can't be opened due to invalid character error code 800A138F

Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.2 r202


  • User Agent: Mozilla/5.0 (Windows NT 6.2; Win64; x64; rv:11.0) Gecko/20120313 Firefox/11.0

More Information

I had iolo system mechanic fix 11 security vulnerabilites and I was able to open it and change the preferences, but it messed up my sytem update. I am using windows 8

  • Top 25 Contributor
  • Moderator
251 solutions 3018 answers

May I ask where you are getting the error message from? Also a screen shot will help if you can do that.

Question owner

It is when I go to windows explorer, users, appdata, mozilla, firefox, default..... Both the Prefs and user folder won't open, so I can't see what the settings are and therefore I can't change the preferences because the error message prevents the folder from opening.

  • Top 10 Contributor
  • Moderator
10756 solutions 96800 answers

I see that you are on a Windows 8 preview, so make sure that you only run programs that are full compatible with Windows 8.

You can do a disk check with the chkdsk.exe program.
If you run the chkdsk.exe program from a cmd.exe Command window then you can read the response from the chkdsk.exe program.

Open a cmd.exe window:
Start > Run: cmd.exe <press Enter>

At the command prompt (>) type or Copy&Paste: chkdsk.exe /f /r <press Enter> (put a space before /f and /r)

If you get something like: Would you like to schedule this volume to be checked the next time the system restarts? y/n then answer the question with "Y" and close all programs and reboot the computer.

You may have to remove the entire Mozilla or Firefox folder in AppData.

Question owner

thanks cor-el, I 'll give it a try it's not a big problem, just a nuisance that I can't fix something and change the preferences. It didn't correct the problem. Thanks anyway.

Modified by dbquick