Connect to one domain and not any others

I have several doains and I have been using SmartFtp for years. Love it!

Recently I discovered that I cannot login to my domains anymore. I have tried turning off the firewall,
restoring my computer, deleteing and reinstalling Smart FTP but no luck. The restore worked the first time
this happened but now my restore points are gone and I can't restore. (<----whole other problem, I know.)

The weirdest part of all is that I can login to one and only one website and upload to it but not to any others.
I can, however, upload to all of my websites from my SmartFTP program on my work computer so I know it is not the server but this computer.

This problem has been persistant for a couple of weeks now so I am desperate!

Please help!

BTW, I did clear all of my quick connect urls so as to give it a fresh try but that did not help either.

Strange very strange that I can connect to one domain and not to any others.
How is that possible?