Thank you both for your replies. I first tried TheRocks's suggestion, but could still not install the policy (same error as before).
Then I tried to run the update_inspect_files command, but got this error message:
[Expert@mgt:0]# update_inspect_files -f
Wrong usage: missing '-index' flag
Help text:
update_inspect_files --help
Please run with the following parameters: [-index <HFA_INDEX>] [-list <input file> (list of .def files)] [-path <path to the .def/_HFA.def files> (if different than $FWDIR/lib)] [-f (to force override)] [-mode <upgrade or export>]
To restore changed files run with -restore [-index <HFA index>].
Do I need to refer to a specific hotfix in order do restore the .def files?