Today, after I started Ubuntu (11.04) I noticed this window immediately after running firefox:
As you can see it is empty. No information about what is probably wrong. I closed the file and tryed to open a page (e.g. www.google.de). But firefox does not show any content. Browsing seems not possible.
I restarted firefox several times but the behavior did not change. Sometimes the this "Alert"-Window does show this text:
Could not initialize the application's security component. The most likely cause is problems with files in your application's profile directory. Please check that this directory has no read/write restrictions and your hard disk is not full or close to full. It is recommended that you exit the application and fix the problem. If you continue to use this session, you might see incorrect application behaviour when accessing security features.
I have enough hard disk space (30 Gigabyte remaining free). I reinstalled firefox by the Ubuntu Software Center, but the problem remained. I don't know how to proceed to track down the error. Any suggestions?