When migrating Public Folder to Exchange 2016. Public Folder Target Agent (PFTA) stops processing when it tries to compact PST file in case of content cannot be fully synchronized. The last log message is the following:
MailContainer::Compact TraceMsg 1702 Starting to compact PST file.
This issue has been verified as a defect and raised as MMEX-1769. Migration Manager for Exchange 8.13 Hotfix (Update_20170530EX) hotfix has been released to fixed this issue which can download here.