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Unable to delete cookies for individual websites

  • 5 replies
  • 2 have this problem
  • 23 views
  • Last reply by Sarabande

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Am running Firefox 29 on Windows 8.1 64 bit.

This arose because a particular website was having difficulty setting a cookie (I think) - FF was giving the error that the website server was redirecting the request in a way that couldn't be completed - but with the caveat that it could be caused by cookies not being permitted. So I tried deleting the cookie for that particular website but FF seems not to comply. It is removed from the list of cookies in the dialog box and I can close the dialog, however if I reopen it the cookie it still shown as present. Doing it a second time doesn't help.

I then found that this doesn't just apply apply to one particular website, it's any website that stores a cookie. Cookies are set to be deleted when they expire as I find it useful for some website to store cookies (I can't seem to find a whitelist which allows cookies to be deleted except for those on the whitelist, this in contradistinction to the blacklist which prevent certain websites from setting cookies at all).

I've tried the following: (1) open FF in safe mode but I get the same result (cookie not deleted) (2) with FF closed rename the cookies.sqlite file out of the way. Starting then with a "clean" cookie file I still get the same result (cookie not deleted). I can confirm the cookie isn't deleted by quickly opening the cookies.sqlite and searching for the website string.

I have tried setting FF cookie "policy" to remove all at the end of session and that works - but it also removes the useful ones as well. Does anyone have some ideas?

Am running Firefox 29 on Windows 8.1 64 bit. This arose because a particular website was having difficulty setting a cookie (I think) - FF was giving the error that the website server was redirecting the request in a way that couldn't be completed - but with the caveat that it could be caused by cookies not being permitted. So I tried deleting the cookie for that particular website but FF seems not to comply. It is removed from the list of cookies in the dialog box and I can close the dialog, however if I reopen it the cookie it still shown as present. Doing it a second time doesn't help. I then found that this doesn't just apply apply to one particular website, it's any website that stores a cookie. Cookies are set to be deleted when they expire as I find it useful for some website to store cookies (I can't seem to find a whitelist which allows cookies to be deleted except for those on the whitelist, this in contradistinction to the blacklist which prevent certain websites from setting cookies at all). I've tried the following: (1) open FF in safe mode but I get the same result (cookie not deleted) (2) with FF closed rename the cookies.sqlite file out of the way. Starting then with a "clean" cookie file I still get the same result (cookie not deleted). I can confirm the cookie isn't deleted by quickly opening the cookies.sqlite and searching for the website string. I have tried setting FF cookie "policy" to remove all at the end of session and that works - but it also removes the useful ones as well. Does anyone have some ideas?

Chosen solution

Note that your System Details list shows that you have a user.js file in the profile folder to initialize prefs each time Firefox starts.

The user.js file is only present if you or other software has created this file and normally it wouldn't be there. You can check its content with a plain text editor (right-click: Open with) if you didn't create this file yourself.

The user.js file is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

You can use this button to go to the currently used Firefox profile folder:

  • Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
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All Replies (5)

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Start Firefox in Safe Mode
While you are in safe mode;
Firefox Options > Advanced > General.
Look for and turn off Use Hardware Acceleration.
Poke around safe web sites and see if there is still a problem. Then restart.

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Unfortunately this seems to have had no effect, even with trusted, safe websites.

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It could be the work of one of your add-ons, or even add / mal-ware. Look thru your add-ons list and make sure you know what each one is there for. Also, check the programs that are on your computer Windows > Start > Control Panel > Uninstall Programs. Go thru the list and use a web search to check any that you don't know what they are.

Troubleshoot Firefox Issues Caused By Malware

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Chosen Solution

Note that your System Details list shows that you have a user.js file in the profile folder to initialize prefs each time Firefox starts.

The user.js file is only present if you or other software has created this file and normally it wouldn't be there. You can check its content with a plain text editor (right-click: Open with) if you didn't create this file yourself.

The user.js file is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.

Delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

You can use this button to go to the currently used Firefox profile folder:

  • Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)
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Hello cor-el,

That was fantastic, it worked perfectly! Thank you so much for that advice. As I recall the user.js file was something I put in for FF3 for a reason which I can't now recall and is now clearly damaging.

Once again, thank you.