Do you have a Dll.xml file?  It should be located in the folder as shown on this screenshot:

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  If you find the file, you can manually put in the text:   <Launch.Addon><Name>XMLTools64</Name><Disabled>False</Disabled><ManualLoad>False</ManualLoad><Path>XMLTools64.dll</Path><DllStartName>module_init</DllStartName><DllStopName>module_deinit</DllStopName></Launch