Here's a simple requirement: connect two Windows 2000 computers using RAS, and two phone lines. Make sure that the connection is always up, and that if by any chance, one of the lines is dropped, it is automatically reconnected.

Sounds simple enough until you try to put it into practice. The Microsoft recommendation is to set up the multilink rules so that the second line is dialed as soon as activity reaches 1% for more than 3 seconds (i.e., the minimum possible) and the hang up rule should be activity less than 0% for over 1 hour.

You do all this and test it, and what do you find? That the second line is hung up after 2 minutes, that's what. Why on Earth would it be doing that?

You may see an entry in the Event Log telling you the reason if not how to fix it: "20164 - The Remote Access Server wants to disconnect a link in the connection to %1 made by user %2 because the bandwidth use is too low." In other words, it's the server who thinks that you're not using enough of the bandwidth and tells your computer to hang up the second line.

So, how can you fix it? Microsoft's Web pages seem helpful, in that they tell you to go to the Computer Management console and open the Routing and Remote Access snap-in... until you find that you may not have a Routing and Remote Access snap-in. That is because you first need to actually install Routing and Remote Access on your server. (You may also need to start the Remote Registry service in order for the snap-in to function.) An alternative is to install the Internet Authentication Service (IAS) optional component through Windows 2000 Setup. Once you have the snap-in, you'll be able to find the Routing and Remote Access Policies entry, double click on the item on the right, find a button labeled Edit Profile, click on it, and finally reach the Edit Dial-in Profile dialog, which has a Multilink tab, which is where you will find that your server is indeed configured to hang up the second line after 2 minutes if activity is less than 50%.

Server, you ask? Yes, server. But you can make a multilink connection between two Windows 2000 Professional workstations, can you not, you ask? Yes, you can. But there's no Internet Authentication Service, or Routing and Remote Access features on a Professional installation, is there? No, there isn't.

So, how can you fix this problem on a workstation install of Windows 2000? I only found one way. For this, you need Microsoft Access, with which you can open the file C:\WINDOWS\system32\ias\ias.mdb (your actual file location may be different depending on where Windows is installed.) Open the Properties table. You'll either find entries in it already that are similar to the following, or you'll need to create them:

As you can probably guess, the msRASBapLinednLimit value is the bandwidth percentage, while msRASBapLinednTime is the duration, in seconds, for which activity must remain below the percentage level in order for the line to be dropped.

As usual, your mileage may vary. In particular, editing ias.mdb can cause all sorts of problems if not done right, including potentially rendering your system unusable. Consider yourself warned.