Details
Turn off the below settings in Customer defaults.
Gateway->General-> Expressions
Show Missing Interpart Expression Part Warnings
Show Referencing Interpart Expression Warnings
Now while opening a part that contains Interpart Expression, a warning message is output
It is expected that there should not be a warning as these options are turned off
Solution
By checking OFF this option, You can disable the warning when the source part is missing but not when deleted . i.e. It has be there in the assembly structure but should not be there in disk.
In that case only, that option is applicable.
Hardware/Software Configuration
Platform: INTL64
OS: windows
OS Version: 1064
Product: NX
Application: DESIGN
Version: V12.0.2
Function: EXPRESSION
Ref: 002-8016692