Error in configuration testing

Hi,

When I test a configuration in Integration Directory, the execution stops at the step of Interface Mapping and gives the error for its interface mapping as -

<b>Interface Mapping <Not found>

Runtime error

Unable to find resource com/sap/xi/tf/_MM_CALC_.class (urn:tbit40:workshop:webapp, 1f08afe1-93ce-11da-ccfd-fb3fac190876, -1)</b>

"MM_CALC" in above is the message mapping object.

The scenario was working earlier and it was not changed also. Still, why this error is coming ?

Regards,