What does this error mean

WEB TMS WEB Core
1

I cloned one of the XData demos to experiment with. When running the client I saw this error once. The second time it was fine.

What does it mean?

Exception EHttpSysSessionException in module sqlServer.exe at 007748BE
Could not add the following Url to the server.
Be sure that you have reserved the Url in Http.Sys with proper permissions.

Url: http://+:2001/tms/firedacsql
Error: Cannot create a file when that file already exists.

3

The error usually indicates that there is already another server running at that URL. It might be in another application or even in the same application.

So make sure you didn't launch the same app twice, or that you are somehow launching two servers in the same app accidentally.