SAP Mail Recipient Configuration

Hi Gurus,

As a security measure, we are maintaining the validity of inactive users, who are no longer working in the company (in USR02 table GLTGB field)

Now, even after the validity is set, if a sender tries to send a sap mail, the system doesn't warn him; the message sends to the inactive users but the sender is unaware of this.

My requirement is to warn the sender with a custom error message:

So I need to create an enhancement in SAP office: SOADRESS.

Can someone pls explain the procedure to do this.

And which FM to choose from:

EXIT_SAPFSSOD_001

EXIT_SAPLSO13_001

EXIT_SAPLSO13_002

Regards

~Kaushalya