Hi - because the failure does not contain a detailed error or error code it is hard to know what caused it without debugging.
What I suggest:
1| Contacting TAC so that they can conduct a proper investigation
2| Check $CPDIR/log/cpd.elg file on the Security Gateway to see if there are any errors given during Install Policy
3| Can you trace any changes that were made between the failure and the last time install policy was successful?
4| Consider reverting to an earlier database revision to see if it solve the issue (Manage & Settings > Sessions > Revisions)