I had trouble archiving 2 large (133 and 149 MB) messages from an Exchange mailbox, no errors in the Event Logs and all other messages archived without issue, dtrace snippet (further log attached) showed errors as below:
CArchivingAgent::MakeItemPendingAndProcessMsg - Com Result [0x80004005]
CArchivingAgent::WriteWorkItemsToQueue - At Default Handler with Error code [0x80004005]
After investigation the cause of the issue was the the MaxReceiveSize and MaxSendSize configured on the Exchange 2010 transport servers. The transport settings are change controlled but setting a higher value at the mailbox level allowed the messages to be archived.
Check the MaxMessageSizeToArchiveMB value in the VAC first.