UDF violation access error
 

hi,
I made a small UDF DEFiNE_TURBULENT_VISCOSITY(name,c,t)
And I interpret without any problems.
But when I initialized, I got this error
FLUENT received fatal signal (ACCESS_VIOLATION)
1. Note exact events leading to error.
2. Save case/data under new name.
3. Exit program and restart to continue.
4. Report error to your distributor.
Error Object: #f

Someone please help me how to solve this problem?