Errors with interpart expressions

[fred2002]

I am trying to create an interpart expression in UG v16 between the top level of an assembly and a component part. I have created an expression at the top level and applied it. When I go to the component part and try to reference this expression using Tools > Expression > (Select expression to be modified) > Create Link > (Pick assembly) > (Pick assy expression) > OK > Apply, I get the following error message: "Invalid Foreign Expression". What is causing this and how can it be resolved? Thanks.

 

[cowski]

Have you created similar interpart expressions before? If not, you may have to enable interpart expressions (it is disabled by default). To enable it you will have to edit your customer default file (see your documentation if this is the case).

If interpart expressions are already enabled, you might try to create the expression 'by hand'. This is the format for typing it in manually:
your_exp=part_name:art_expression+...

Hope this helps you.

 

[fred2002]

Thanks for the suggestion. I have been able to create interpart expressions in the past and that is why I have found this error puzzling and annoying. Manual input also brought up the error.

Now the good news - by some miracle, I managed to get the expression to work. However, I still don't know why the error comes up or what I need to check in order to rectify it so any answers or explanations will be gratefully received.