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TestShell Studio or Runner loads many different internal plugins on startup.
Sometime, failure on one of those plugins will generate an error that will pop up as a warning message that could be quite elaborated, as below:
Clicking OK will launch Studio (or Runner) but in some cases - it will not be usable at all.
To understand what went wrong, it is enough to look on the first line of the error message - this is because when Studio fails to load a plugin, the rest of the plugins will fail to load as well.
In our example, it's a failure in the LibrariesPlugin - An entry with the same key already exists.
This happen when, for some reason, Studio have a duplicated library in it cache.
It can happen if, for example, you were working offline on a library called Test1, closed studio, and loaded it again online against a TestShell Server that contains a library with the same name.
In this case, when studio will try to cache the library Test1 from the server, it will cause an error because a Test1 library already exists in its cache.
To solve it, you can try to work offline and rename the library, or rename the Libraries cache of TestShell Studio at:
C:\Users\[user]\AppData\Local\QualiSystems\Libraries
Rename that library to Libraries_old and see if you can now restart the application.
If all works fine, it is recommended to delete the Libraries_old folder to avoid cluttering.
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