tasks don't work

[desertimp]

Recently my tasks throughout a shared database stopped working
properly. When a user tries to assign a task, they get a pop-up
message saying "Business Contact Manager for outlook could not
complete your last action or actions. Please try again."

The weird thing is that it still emails the task to the person it was
assigned to, but does not show up in the history for the account/
opportunity that it was assigned for...

If anyone could shed some light on my situation I would greatly
appreciate it.

Thank you,

Jon