incoming calls won't go through ("all circuits are busy")

[JohnnyTooBad]

I had to unplug all my computer equipment to put it all back into the computer desk after putting new floors in. When I plugged it all back in, I can make outgoing calls, but when I try to call from my cell phone, I get "All circuits are busy, please try again later. Message 8 (switch?) 18-9". It sounds like she's saying "switch", but was fairly unrecognizable.

I have tried resetting my router and my Grandstream (twice) by pulling the power plug and waiting 30 seconds. I was considering hitting the reset button, but the last time I did that, I screwed something up and was told by a Tech not to do that, and had to reload some software.

How do I fix this?

Thanks.

-John