If I use "\\abc124\sharename", I can open up the share.
If I use "\\abc124.domain.local\sharename", it says remote machine not available.
nslookup resolves correctly both forward and reverse.
I managed to duplicate the problem on another server in the domain. So I suspect it may be something with Group Policies. But I didn't set them up, and I have no idea where to look. Any hints would be greatly appreciated. Thanks!