We have a user that uses the Sonicwall Global VPN to RDP from his MAC book off site into his Windows workstation on site. All of a sudden a few months ago, his connections were sporadically not let him access the remote desktop. We are able to RDP at anytime from another Windows pc however. What could be the issue when going from the MAC RDP AP?
What version of Microsoft Remote Desktop are they using? The older version you can download from MS's site, or the newer version from the Mac App Store?
MacBooks can run Windows via Boot Camp. Maybe set him up with that to connect in?