User error?

Check if you inadvertently indicated they are not doing business/they are exempt.

Oregon has been known to be wrong....   so double check all your info.

I filed a partial year return for a Sub S Corporation showing 10.83% allocation. They made it clear that the Sub-S owed a minimum excise fee of $150.00.

I did. Tend to do that before I panic and go to the community. 

I verified that I did indeed say we did business in Oregon and the return clearly shows the allocation. As a 1120S I did not think to challenge the program's calculation of any tax due. The letter from Oregon states that there is a calculation error on the return and that the minimum Excise tax is due. If a minimum is due on a Sub S in Oregon, it seems it should have popped. 

We are just users of the software. If you think there is an error in the software you will need to contact Support.