Non Admin users are not able to access custom module


I have few custom modules in Sugar Professional 6.5. However, only one custom module is not accessible for non admin user although their roles have access for the same.

I have tried below:

1. Repaired Roles

2. Reset User Preferences

But still non admin users cant access particular custom module. System gives message "You do not have access to this area. Contact your site administrator to obtain access."

What else can be done to resolve the issue?