When you try to run Tableau tabcmd from a new command prompt window on a computer where tabcmd is already running in an existing window, the command fails and one of the following errors might occur:
500 Internal Server Error
or
No valid session found (errorcode=46)
It is not currently possible to run multiple instances of Tableau tabcmd from a single computer.
In order to resolve errors such as "No valid session found" or "500 Internal Server Error" when using Tableau's tabcmd, review one of the following workarounds:
001473231

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