A couple of computers, both Win7-64 can connect to shares on a NAS server, at least most of the time. At random intervals, these Win7-64 computers cannot access some shares but can access others on the same NAS. When access is denied, a dialog box appears saying "\\myServer\MyShare02 not accessible...you might not have permission to use this network resource..."

Other shares, say \\myServer\MyShare01, ARE accessible from the affected computers and yet other computers CAN access the affected shares.

Reboots of the affected computers seem to allow the affected computer to connect to the affected shares - but then, getting a cup of coffee seems to help too.

When the problem appears, the network seems to be ok e.g. the affected computers can access other shares on the affected server and can ping etc. Also Other computers can access the affected shares.

The NAS server is a NetGear ReadyNas Pro. The problem might be on the NAS side such as a resource limitation but since only 2 Win7-64 PCs seem to be affected the most, the problem could be on the PC side - I'm not sure yet.

I of course searched for solutions and found several tips addressing initial connection problems (use correct workgroup name, use IP address instead of server name, remove security restrictions etc) but none of those remedies address the random nature of this problem.