I have seen this error occur in two different scenarios. Sometimes (and
seemingly randomly) it occurs when i click on the data tab - i get the error
& no ribbon. I hit ok and then choose another tab - select the data tab - no
problem it works.

This is irritating but i just thought it would disappear when the patches
start coming out.

Now - i add-in solver. I have the solver button. I hit solver - i get the
error 400. No work around seems to open solver.

Anyone find a solution?

Lauri