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I downloaded Taggtool5Server64NoJava.exe, copied it to my air-gap computer, ran the install, and still no joy. The Taggtool 5 Server Setup Wizard appears and the status bar progresses to the right until it reaches about 80% where it says Starting Services. It sits there for about five minutes then I get a new popup titled Taggtool 5 Server that says:

Service 'Taggtool 5 Server' (Taggtool.exe) failed to start. Verify that you have sufficient privileges to start system services.

I click the Retry button and, after five more minutes, I get the same popup. I opened Process Explorer and I can see, under services.exe, that Taggtool.exe tries to start a few times.

That bit about "sufficient privileges" may be the problem. I'm installing this on my work computer and our IT department keeps tight controls on things. However, I had no trouble installing the desktop search program called "Everything" which runs as a service. I can see Everything.exe in Process Explorer under services.exe.

I tried running Taggtool5Server64NoJava.exe as administrator and I get the same results.

Any ideas?