I'm not sure if this will apply in your situation but I recently install FMSA v12 and was getting random 802 errors for custom web publishing clients. There was an issue with the license keys that were intially released last year:
that could cause this issue. You'll need to check with FMI to see if you have one of the keys that needs replacing, but worth ruling out up front before you spend hours like I did trying to troubleshoot this.
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