SSID must be a valid CALPADS SSID in the ODS.

In other words, you are submitting a file with an SSID # (State Student Identifier Number) that is not recognized yet by CALPADS.  It is either a typo in your SIS system, or the SSID # may have been recently retired, or there is some other error.

Verify that SSID provided in the submission is valid by searching for it in CALPADS. LEAs may need to obtain new SSIDs and update the local SIS with the new data.