Server Busy Error at Start Up

When I start up my computer, I just started getting a dialogue box that says "SERVER BUSY", and I can click either a "Retry" or "Switch to Another" button. When I click on the Switch... button, it goes away no problem, but I don't understand why the dialogue box seems to have suddenly appeared at start up.
I 've seen references to this error when people launch specific software, but I'm getting it at start up.

Any help input is appreciated, as usual.

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