Loss of code

Hello there!!

I've just installed the developer studio 7.0.11 in a computer, then I imported a project but I try to change some things while moving between tabs (for example from the source to context tab and back to the source tab) then I lose the changes to the code... I'm sure it's not normal

I thought I could be because of RAM lack, but I've checked the task manager and it says that the computer has more memory than it requieres (the computer has 1GB of RAM and is using 700MB)

Do you have any idea of what could be happening?

Thanks a lot!