UPdate all Dependencies(CVF)

Hi

I use Compaq visual fortran 6.6c.
Very often, I need to look for the definition of a subroutine/function
through this IDE.  It's quite convenient.
However, sometimes I found it showed "the symbol of some subroutine/
fun. is not defined."
It's quite annoying?
Does anybody know how to fix this problem?
I have already done the UPdate all Dependencies...

Mike