An annoying issue kept recurring in distributing data from our main SCCM server to a remote distribution point.

The moment a file was fully transferred, it would be deleted by the DP and the PkgXferMgr.log would show the following:

Failed to get object class
ExecStaticMethod failed (800706ba) SMS_DistributionPoint,AddFile
CsendFileAction::AddFile failed; 0x800706ba
Sending failed.

After crossreferencing the time of failure with our firewall logs, we found a rule blocking RPC traffic down from the SCCM server to the distribution point.