Hi Bill,

Here are a couple of things to look at:

• First, for your version, I believe you have listed the Web Server version. Instead, go to Administration, Utilities ,Update and under Dataset select your folder. On the about screen, you'll find your Release information in the Product / Application area. 
• TRTVENLIVV is an entry point and is using the code differently.
  • Were any changes made?
• Do you have any leading or ending spaces on the dimension? 
• If you try a different dimension value does it work? Isolating whether the part, dimension or customer is the issue.
• Does this work on your test folder?
• Take a look at the blog Troubleshooting tools of the trade 

3 Years later - I'm running into this exact issue. In my case the process works fine in Sage 11 but in the (almost) latest Sage 12 environment it fails with this error, so must be something changed along the way. Did you find a resolution, and if so happen to recall what it is?

-- update

Found the answer in another post!

 Shipment validation using TRTVENLIVV fails with dimension values 

This worked for me, I just updated my existing script with the 2 new calls.