I had an issue come up yesterday where I couldn't connect to my windows machine through the remote desktop utility for Mac. Everytime I tried to connect it would attempt to connect for about 20 seconds and then come back with an error message.
The error message said something like this: TSC_IDS_SECAUTH_AUTH_ERROR_INFOR
Not all too helpful. I rebooted my mac, this didn't help. Then I rebooted the PC, also didn't help. Searched online and found ABSOLUTELY no google result with just the above string of text. So after I found the solution, I thought I would post this to help anyone else that might come across this issue.
The solution was to go into Control Panel -> System -> Remote Settings. Then disable remote connection settings. After I disabled remote connection I attempted to connect from my Mac and I got a different message this time. Good deal! This means it was definitely an issue on the PC side. Then I re-enabled the remote connection settings for any version of Remote Desktop. Then attempted to connect again from my Mac, and viola! I was in. Something must have just gotten screwed up in the configuration. Disabling and re-enabling did the trick.
Hope this helps!