Thanks LaPastenague. For the record, my TC is the old model with 2Tb (not the tower one).
Following your previous advice (and seems to be the quickest way by now to solve) I decided to restart from scratch and reinstall windows.Also because I noticed that i could access via browser running windows on safe mode.
After I did that, I first installed the time capsule (even before doing all past windows updates) and it worked perfectly like before. Even with a long name for the time capsule (instead the short 8 letters).
Having done that, I slowly started uninstalling bloatware and installing my basic software suite. Rebooting every time to check if TC was still mapped.
After some time I found the evil do-er, it was Avast. Right after I installed Avast anti-virus I start having the same message: "Could not connect to the disk. Make sure NetBIOS is enabled and try again (53)". Again, I turned all Avast protections off and the error persisted. Decide to uninstall Avast and TC started to work as good as before.
Very strange as I had disable everything on Avast before and it did not fix. Probably something to do with its installation, which is also strange, as I was running Avast with the original windows installation and never bump into this issue.
I am still mid process on installing everything back, but I will report back if something derail.
Lessons learned: 1) Guess now is the best time to stop using those pesky anti-virus and 2) Never again I will use a TC as a windows backup solution.