Thank you for the speedy reply!
I have downloaded and installed version 3.0.1 but problem still exists. I am running Sequel 3.0.1 on a PC with Windows 7. Also, I have filled out and sent a support request form.
This error message window has popped up a couple times in the past, but I was able to "fix" it by closing out of Sequel, restarting my PC, and then reopening Sequel. After taking those steps it allowed me to save again. This time, however, it is being quite persistent.
Again, thanks for the quick reply! Any further advice you could offer would be greatly appreciated.