Just wanted to share a fix for this error when trying to RD to an XP
box. I spent a few days trying to fix it and there were a ton of
articles and blogs that offered several solutions that didn't work.
Most were geared toward the Terminal Services server. Mine was a client
issue.

I am an admin on a LAN that has a few hundred XP boxes. 2 of them gave
an error when trying to connect via Remote Desktop:

The connection was ended because of a network error. Please try
connecting to the remote computer again

A frequent cause of these problems stems from issues with some registry
values in the TermService\Parameters registry key. To fix, select the
following key:
HKLM\System\CurrentControlSet\Services\TermServices\Parameters

After doing this, delete the Certificate, X509 Certificate, and X509
Certificate ID values, and restart. The key will be regenerated. I only
had the Certificate value, but should any of these exist, delete and
restart.

WARNING: Always back up the registry before making changes.

Thank you for sharing this with us.

Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
  Just wanted to share a fix for this error when trying to RD to an XP
  box. I spent a few days trying to fix it and there were a ton of
  articles and blogs that offered several solutions that didn't work.
  Most were geared toward the Terminal Services server. Mine was a client
  issue.

  I am an admin on a LAN that has a few hundred XP boxes. 2 of them gave
  an error when trying to connect via Remote Desktop:

  The connection was ended because of a network error. Please try
  connecting to the remote computer again

  A frequent cause of these problems stems from issues with some registry
  values in the TermService\Parameters registry key. To fix, select the
  following key:
  HKLM\System\CurrentControlSet\Services\TermServices\Parameters

  After doing this, delete the Certificate, X509 Certificate, and X509
  Certificate ID values, and restart. The key will be regenerated. I only
  had the Certificate value, but should any of these exist, delete and
  restart.

  WARNING: Always back up the registry before making changes.

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