Public Folder Servers assigned to ESMGroups other than "default" will not be processed by any ESM instance despite having been assigned a Public Folder policy.
Product Defect
STATUS
Waiting for fix in a future release of Archive Manager.
WORKAROUND
Assign the Public Folder server to the "default" ESM group. Alternatively replicate all public folders to an Exchange server which is in the "default" ESMGroup.