I have 2 Windows XP PRO SP1 boxes on a small home network of 3 computers (other 1 is laptops). The 2 XP boxes have static Public IPs on different ranges and subnets (that's just how my ISP gave them to me). So I use NetBios to share files 'tween the two. Both computers have shared folders that the other computers utilize, and have for over a year.
 
This morining I go to use a share (on either computer) and now get a login prompt titled "Connect to computername" that looks more like a dial up prompt. The user name is greyed out but says COMPUTERNAME\Guest. NO PASSWORD WORKS.
 
Here's what I have already tried that has not worked.
 
1. Shutting down the entire network, including switch and cable modem.
2. Checking and making sure the Guest account is DISABLED, like it was.
3. Going through Network Neighborhood
4. Checking user account passwords and making sure password does not expire.
5. Killing any 3rd party programs from startup.
6. Disabling connection sharing and firewall.
7. Removing and creating a new share.
 
No new programs were introduced, no viri found, nothing was changed at all, this happened overnight!!!!!!!!! Please Help.