If you are not able to access IS Admin user I don’t think you can be able to access unless you remember exact password or any typo during password change?
Also editing IntegrationServer/config/users.cnf file might not help.
Did you tried using any other user having Admin rights and so can change the Admin password…I am sure you might have thought on this and just making sure to bring this dumb question:)
Better check with SAG support on this to resolve:
HTH,
RMG
#Integration-Server-and-ESB#webMethods