Log Shipping Fails with CONTINUE_AFTER_ERROR DR plan for primary database in a private hosted cloud environment. The primary is a hosted physical server. The secondary is on another network, same domain. Version is SQL Server 2008R2 (10.50.2550.0) Enterprise. Compatibility=2008.

Log Shipping runs fine for a few restores, then I come back the next day, and I see "A previous RESTORE WITH CONTINUE_AFTER_ERROR operation left the database in a potentially damaged state." And the restore job continues to fail. No further restores go through.

I checked the primary db with DBCC CHECKDB and there are no errors reported. I reconfigured LS twice, and the last time, added a 5-minute delay for the restore job. Same thing happens every time. It runs fine for a few restores, but then fails.

I could really use some help knowing where to look for the issue.

Graeme 
PS: This question was previously posted on SQL Server Central, with no responses. At the request of an expert, I am moving it here. Thanks again.
Do a FULL backup of the primary DB (now or whenever), copy that backup file over to the secondary server, then restore that to the secondary DB in standby mode. 

Afterwards, see if your LS jobs run successfully on secondary once you get enough fresh logs to apply to it.