PVTree (org.csstudio.diag.epics.pvmanager.pvtree) fails to discover the tree if the PV it is looking at is in an error state.
The top node is displayed as:
<pv_name> (ai [MAJOR,LINK_ALARM]) = 0 [MAJOR,LINK_ALARM]
The PV analysis assumes the record-type string just contains 'ai'.