excel crashing when I use scenarios tool
 

I am using the scenarios tool in excel to run several different
scenarios. It was working fine two days ago, but now every time I run
the tool it crashes excel and I get the following message:

CiceroUIWndFrame: EXCEL.EXE - Applicaiton Error

The exception unknown software exception (0xc0000409) occurred in the
application at location 0x303925e9

Scenario manager works in some of my other spreadsheets but not this
one. However, when I put my scenarios in manually it works fine. It
also works fine when I go through each scenario and click "Show". It
crashes only when I run the Scenario Summary.

Any ideas?