hi! i am using chrome browser for a long time, i had no troubles until now! sometimes, when i close the browser and reopen it, my themes, extensions have all disappered. it goes back to defult mode. my settings also goes t=back to defult mode. i have to re-add and change my settings! why is this so? and how can i prevent this or is there a way to have a backup copy! thanks

OS and Chrome version would help us help you

windows 7 professional and chrome 4.0.249.89 unknown (38071)