To help block spam, the LPL mail server filters incoming mail by consulting worldwide spam blocklists. Connections from systems listed in those databases are rejected.
If you are an LPL user, you can use our online search tool to check whether a sender's IP address or domain is on one of the blocklists that we consult: LPL Email Blocklist Lookups
If you would like us to unblock a sender, please send an email to sys (LPL Systems), specifying the from-address that cannot send. LPL Systems staff will help diagnose and correct the problem.