If a dialog appears containing “Invalid Class String”, with the error code “CO_E_CLASSSTRING“, followed by RxUniverse crashing, you must run C:\rxuniverse\run8\marshal.exe /RegServer in an Administrator command prompt in the Rx-Universe install directory.
To run a command prompt as administrator, hit the Windows Key, search “cmd”. Right click on “Command Prompt” in the search results and click “Run as Administrator”.
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