Setting up a VPN (Virtual Private Connection) is a trivial matter to set up and provides an encrypted tunnel (link) for remote workers. If you are running Windows Server it is set up under Routing and Remote Mangement. It can even be set up on a standalone XP (probably 2000 and lower as well) workstation by creating an advanced connection in the Create New Connection wizard (Accept incoming connections.) You’d just have to route port 1723 (default PPTP port) to whichever computer is accepting the connections. You’ll also need to have a user set up to be able to connect remotely – this is done under the Dial-in tab on their user account.
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I usually recommend Logmein.com. You can setup a free account and give the engineer access to it. When he is done trouble-shooting..simply delete the account and uninstall the software….They have a number of good products.
Guys I would NEVER NEVER suggest that you use sites such as logmein/gotomypc to access an Internal server…. You’re allowing access from yet ANOTHER 3rd party into your network by doing this…. it only takes one disgruntled employee at a 3rd party service to do something stupid and bang goes your network security!!
You need to set up a fully encrypted VPN, send them over the client or however you choose to do it, and pull them through your firewalls with severe restrictions!! You can always set up times for this access to reduce risk.