Problem: "All of sudden" today when I started Oracle Forms Builder 9i (yes we are using 1996 technology) I got Microsoft Visual C++ Runtime Library error Assertion failed! FRM-10039:
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Cause: A new Java Virtual Machine (JVM.DLL) was pushed out to our PCs. Users were having problems with it. While working out the user's JVM problems, I made a copy of JVM.DLL in the directory where I start Oracle Forms Builder. When Oracle Forms Builder was starting it was using the local copy of JVM.DLL and not the copy in the directory where I installed Oracle Forms.
Fix: I deleted the copy of the JVM.DLL that was in my local directory. Now Oracle Forms Builder is using the JVM.DLL that was provided by the Forms installation.
Summary: If you get the Assertion Error when starting Oracle Forms Builder, check to see what JVM.DLL file is being used by Oracle Forms.