• Make sure that you not run Firefox in Private Browsing - Use Firefox without saving history mode
• In Private Browsing mode some menu items are disabled (grayed) and features like visited links are disabled and not showing
• You are in Private Browsing mode if you see "Tools > Stop Private Browsing", possibly grayed

See Private Browsing - Use Firefox without saving history and http://kb.mozillazine.org/Issues_related_to_Private_Browsing

• You enter Private Browsing mode if you select: Tools > Options > Privacy > History: Firefox will: "Never Remember History"
• To see all History settings, choose: Tools > Options > Privacy, choose the setting Firefox will: Use custom settings for history
• Uncheck: [ ] "Automatically start Firefox in a private browsing session"

I'm NOT running Firefox in Privat Browsing mode. by the way, when I launch Firefox from the Terminal using "sudo" everything is working. maybe there is some problem with access?

Memory cache device

Number of entries: 55 Maximum storage size: 18432 KiB Storage in use: 301 KiB Inactive storage: 301 KiB

List Cache Entries Disk cache device

Number of entries: 82 Maximum storage size: 102400 KiB Storage in use: 1236 KiB Cache Directory: /home/username/.mozilla/firefox/g4h2tnrc.default/Cache

List Cache Entries Offline cache device

Number of entries: 0 Maximum storage size: 512000 KiB Storage in use: 0 KiB Cache Directory: /home/username/.mozilla/firefox/g4h2tnrc.default/OfflineCache

List Cache Entries

Are any of the websites you visit even setup to use the offline cache?

http://weblogs.mozillazine.org/roc/archives/2007/02/offline_web_app.html

https://developer.mozilla.org/En/Offline_resources_in_Firefox

There's no problem with Offline cache. The Disk cache is not working until I launch Firefox from super-user. This happened after the last update to version 3.6.9. With previous version there was no problem! Maybe there's some problem with rights?

One more thing about offline cache - there's no such directory it's using (I couldn't found it).

the problem was solved. I've created new account and showed a new path to another folder. now everything is OK! thanks to all.