I've been doing flow simulation for the last couple weeks with no issues but today I can't seem to open it.  I've used the same method for the last couple weeks to open it, i would go to Tools --> Add-Ins --> and check SolidWorks Flow Simulation 2014 on the left and click ok.  For whatever reason, this no longer opens the flow simulation tab and I go back to my normal screen.  Is this a common issue?  How can I fix it?