keep losing file server in Mac OS

I recently did a mac software update to 10.5.4, and keep losing my connection to the file server I use (which is simply an SMB connection to a windows desktop machine across the office). It might be after being connecting for 5 mins, or an hour and a half. This never happened in 10.5.3 or lower. I was blaming Mac and spent an hour on the phone to their tech support (they never have a clue if you ask them anything difficult). But I realised it only happens when parallels is running. However, the guest OS remains connected to the file server. Anyone else see this happen? Any clue as to how to resolve it?

It also happens in a second, test account, which I set up to see if that might resolve the issue - again, when Parallels is running, Mac OS drops the connection to the file server.

Using Mac OS 10.5.4, Parallels Build 5608, iMac 2GHz Intel Core 2 Due with 2GB RAM

 

You're probably using shared networking in Parallels (the Virtual machine is in a subnet, NATed, of the host machine, sharing the same IP in your LAN), try using bridged networking (the guest(s) and the host will have different IPs in the LAN).

 

that fixed it - thanks!