When I created the WRC file I used SI (MM).
Now several months later and several different projects later I am coming back to this WRC calculation to update the results and when I open the file it is now in SI units (ie cm).
How do I change the file back to SI(mm) units?

Anyone?

Go to the CAESAR II configuration (the Database pane) and change/verify the units.

Okay,
From the home screen, I go to the Configuration Editor, then the Database Definitions. The units are MM.FIL

Then from the main menu I go to Analysis, Choose WRC and open the file. Then I go to the Vessel tab and the diameter is 89.6cm, the wall thickness is 1.6cm, the corrosion allowance is 0.6cm, etc. etc.

What is wrong?

Okay,
From the WRC menu I opened a different file. It is in imperial units?
So I opened another different file it is in mm units

Is there any way to change the units of an existing WRC file??

From the main menu if I go to Utilities and choose "Change Model Units" I cannot even select a WRC file.

I really don't want to re create my WRC analysis from scratch I have 4 nozzles in this job and each nozzle has 5 different cases to analyze.

For future reference for anyone who finds this post.
If you are having this problem and creating a WRC file in a subfolder of the project. To make sure the WRC file is in the same units as the Caesar file do the following
- Open the folder with the Caesar files
- find the caesar.cfg file
- copy this caesar.cfg file to the sub folder

Now when you create a WRC calculation in the sub folder, the WRC file will have the same units as the caesar file