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Why do more empty, localstore.rdf and perf.js files appear in my profile everytime I open and close Firefox?

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  • Last reply by CowDoc

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I have hundreds of empty localstore{xxx}.rdf and perf{xxx}.js files in my profile folder. Where {xxx} denotes a number. New, higher numbered files appear every time I open/close firefox. There ate two pref files (perf.js and perf1.js) which are not empty. There is one localstore.rdf file which is not empty. All other files are zero byte files.

Also, my toolbar customizations will not stay put. I have to re-customize the toolbar regularly. Erasing all of the localstore and perf files in case of a corrupt file does not help.

I have hundreds of empty localstore{xxx}.rdf and perf{xxx}.js files in my profile folder. Where {xxx} denotes a number. New, higher numbered files appear every time I open/close firefox. There ate two pref files (perf.js and perf1.js) which are not empty. There is one localstore.rdf file which is not empty. All other files are zero byte files. Also, my toolbar customizations will not stay put. I have to re-customize the toolbar regularly. Erasing all of the localstore and perf files in case of a corrupt file does not help.

Chosen solution

That suggests something is preventing Firefox from modifying those files. This usually happens when anti-virus software keeps a lock on the files.

localstore.rdf is the file that keeps your toolbar customizations. Since Firefox can't modify it, your toolbar customizations are lost.

A less likely cause is a Read-Only attribute or permissions issue.

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Chosen Solution

That suggests something is preventing Firefox from modifying those files. This usually happens when anti-virus software keeps a lock on the files.

localstore.rdf is the file that keeps your toolbar customizations. Since Firefox can't modify it, your toolbar customizations are lost.

A less likely cause is a Read-Only attribute or permissions issue.

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Excellent answer. Especially since I was completely vague on system and OS info. My apologies.

Yes, it was a Windows 8.1 read-only permissions issue. For some reason this version of Windows sometimes treats my Administrator account like a User account. It is causing other minor problems as well. I had to allow all Users full permissions for the Firefox profile folder, sub folders and files. It's not the most secure arrangement, but it will work for home use.

Thank you for the suggestion and prompt reply.