I would suggest reloading the OS. here is how to do this:
How do I upgrade the OS on my BlackBerry? - BlackBerryFAQ
You don't have to upgrade, use the same OS version as you are running currently.
When I remove apps to free up memory, I create a file on my laptop called "Revomved <OS Version number>", and migrate the code there instead of deleting it. That way, I have it if I need it again.