Launching X1 does nothing

I just installed the latest beta release for the first time. When I try to run X1 beta, the cursor spins for a few seconds, then stops spinning, and nothing is actually launched. The X1 Indexing Master Service is not running, and when I try to start it I get an error dialogue that says "The X1 Indexing Master Service on Local Computer started and then stopped. Some services stop automatically if they are not in use by other services or programs."

Any ideas on what to look for or try? I'm using Windows 7 x64. Also, I have X1 6.7.4 running, which according to what I've read here is OK as long as I turned off indexing, which I have done.

Thanks in advance for any suggestions.

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