Thunderbird re-setting prefs.js

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Joined: August 24th, 2019, 1:46 am

Post Posted August 25th, 2019, 3:35 am

My wife is getting increasingly irritated by opening Thunderbird and finding that it is as if she is just starting with the program from scratch and has to add new addresses. This is because the prefs.js file has reset itself to the initial value of about 5k. We can correct this by copying prefs.js from a backup ( we back up daily on shutdown) and all is well. But then, after a few weeks, Tb does the same again and we have once more to copy over the prefs.js file from the backup. This is getting boring and time-wasting. Does anyone have any ideas as to why this is happening (new version of TB, deleting cookies,etc.) and/or how we can prevent this? We have not installed any new programs recently and TB has always worked fine in the past. We do run Registry First Aid from time to time and this does make (one hopes, safe) changes to the Registry. Help, please. Many thanks.


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Post Posted August 25th, 2019, 4:32 am

Something outside of Thunderbird seems to be impacting that file. Do you have any clean-up programs (such as Cclean) running on that computer?

Note that the issues you report are not related to any Windows registry entries so Registry First Aid will not help and could be problematic in this case.

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Post Posted August 25th, 2019, 5:36 am

We use Glary Utilities but only to clean temp files; we've been using this for several years without any TB issues. Otherwise only Superantispyware and Malwarebytes from time to time. Thanks for clarifying about Registry First Aid. I could always run RSA and see if the prefs.js issue recurs?


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Post Posted August 25th, 2019, 12:18 pm

When the file is reset does it become completely empty or does it become a small file with generic information? In the latter case you see a few generic settings but nothing that mentions your email address.

Did it run the new account wizard? If so see if your address book still has your contacts. I'm wondering whether the prefs.js file became corrupt or Thunderbird lost track of what profile you are using (which would cause it to run the new account wizard and create a new profile).

See if there is a file in the profile with a similar name such as prefs-1.js or prefs.bak. It might be a backup of the original prefs.js that Thunderbird created. ... y_prefs.js

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Post Posted September 30th, 2019, 10:00 am

An update on this problem which has not gone away, whatever I do to try to find out the cause. I am still copying prefs.js from a backup (done on shutdown the last night) and this then allows TB to open as if nothing had happened. Today, however, I copied the file over while Tb was still open in another window. When I closed the Roaming folder and then re-opened it again immediately, prefs. js had reverted to the basic 6kB and the file copied over from the basckup had gone. No other files from other software were changed during this procedure. Repeating this performance twice with TB open resulted in the same thing. If, however, TB was closed before the copying was done, then TB opened with all emails (etc.) in place. Can this still be other software (such as Skype running in the background) or is it now much more likely that it is something in TB itself? I am loath to uninstall and re-install but would welcome opinions, please. Many thanks.

PS. to moderator (above)
1. When the file is reset it becomes the same file just under 6kB. I haven't looked at its contents.
2. I know when this problem has arisen because TB opens with the wizard asking for a new account to be made.
3. How could TB lose track of my profile? There is no other profile in the Roaming folder.
4. There are no other files with names in any way like prefs.js in the Roaming folder.

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