Lost LAN Connection in MS Exchange 2003 network

Question

Hi everybody.
I have  a connection problem which my ICT consultant can't solve or even figure out the cause.
In my company there's a MS Exchange 2003 network. I'm the only one running a Mac (Air bought in early 2011), as the others need to work on Solidworks and need Win machines. In order to connect with email and calendar I'm forced to use Parallels Desktop with Win7 installed to use Outlook and Access for our Internal Self made database.
What is happening is that sometimes when connected through WiFi the server connection is lost, causing loss of work if I had some files open from the server.
Considering that we have some interferences in our area I got the USB Ethernet adapter.
Worse than ****.
When cable connected the connection to server is lost every minute, not only if the Mac goes to sleep, but even during normal work. Unless I "stimulate" the finder every 30 seconds the server connection get lost, sometimes is sufficient to click on the saved preferred positions in the side bar to wake it up, but most of the times if I'm working on files on the server this is not sufficient and the job done is lost.
Also this sometime cause a major failure in the system and I'm forced to shut down the Mac by holding the button.
Any clues?
Thanks

Answer 1

Thanks for the help on making restore points, and on getting Boot Camp 2.1; I recently updated Apple Software Update to 2.1.1, so that's working, and it did suggest BC 2.1 as a downloadable. I'll probably do it manually, though, just to be on the safe side of things, as I don't trust Software Update even in OS X for most things (except to tell me what updates are available; I usually download and install everything manually anyway). Windows Update is a different matter, as I can't get most of the patches it offers by myself (not that I haven't tried--most are available only through the utility).
As for backing up and restoring from a clone on a second hard drive: I can't afford to do that at the moment, as I can't afford the hardware, software, or time needed to prepare a clone backup. And besides, as I said before, I don't do enough in the Windows partition that demands such backup work be done. I use Vista primarily for things I can't do in OS X, with Windows-specific apps.
Still not sure how to go about updating the LAN port driver, or if it even needs to be updated. If BC 2.1 doesn't do it, I'll look up the vendor through whatever link Windows Update provides for me. And I haven't received any word from Verizon about my modem needing a firmware update, but then again I haven't contacted them about it yet, and I'm not sure I need to, or if it really needs to be updated. I'm just hoping that if the connection drops again that it won't be necessary to update or replace the modem, that the problem remains in software. (Of course, I'll take whatever precautionary measures I can, but I can only do so much myself.)