SP3 to the rescue... maybe.
But it looks like the recent release of Windows XP Service Pack 3 has cured this problem as a small bit of blurb accompanying the release says:“Black Hole” Router Detection - Windows XP SP3 includes improvements to black hole router detection (detecting routers that are silently discarding packets), turning it on by default. -Microsoft.com, Overview of Windows XP Service Pack 3.pdf, page 7
To summarize things in layman’s terms, when a sustained connection is made between your computer and a server of some sort, packets of data are regularly sent back and forth. The path between your computer and the server can be comprised of many different routers delivering the information from one part of the digital world to another. If, along the way, one of those routers finds a packet that it decides is too large to pass on, the router should either fragment the packet or at least inform the sender that the packet was not forwarded.
Sometimes a router will simply erase or drop that packet leaving the sender and recipient clueless, which causes problems in large data file transmission, encrypted data sending, and login attempts. This is a black hole router instance. They can be the result of a malfunction, malicious intervention, or improper setup. SP3’s black hole router detection automatically uses, what used to be a complicated process of pinging and adjusting, to identify these problems before sending data and if necessary and possible, redirecting traffic around such routers.
You can find more info on this issue in the MS article: http://support.microsoft.com/kb/314825
If you have not already updated, hopefully this will save you a lot of grief.
