All the tools are gon sudenly

[Galya5E25]

when I open illustrator there is an empty page without any editing tool (all options are gone!)
I tried to change in Window → Workspace and nothing. Tried to click Tab.
I played with the options in Window and some of the tools came back, but once I closed the program and open again there are no tools!

I'm working in illustrator daily and it happens suddenly when I closed the program and open again after few hours.

[Mohammad.Harb]

Which version ? Which operating system ? 
is your graphic card driver up to date? 
have you tried resetting preferences settings?