Typically you can uninstall with the zpm "uninstall zpm" command, but note that an IPM version <0.10.7 may show spurious errors that can be ignored. However, depending on your configuration, you may need to perform extra steps.

1. In the IRIS terminal, call do $SYSTEM.OBJ.DeletePackage("%IPM")
2. In the system management portal, delete any IPM mappings from your namespaces
3. In the system management portal, delete all the IPM* globals

IPM's ORAS support depends on Python packages installed into <iris>/mgr/python. On Windows, those files can end up with permissions that non-elevated processes can't read. Commands that use an ORAS repository, such as search or install, then fail with an error like:

ERROR! ObjectScript error: <PYTHON EXCEPTION> *<class 'PermissionError'>: [Errno 13] Permission denied:
  'c:\intersystems\iris\mgr\python\oras\__init__.py' - Import

The error may show <SYNTAX> instead of <PYTHON EXCEPTION>, or a ModuleNotFoundError for oras if a whole directory is unreadable.

As of IPM 0.10.10, IPM resets the permissions of the packages it installs into mgr/python so they inherit the directory's permissions, and reports this failure as "Unable to read IPM's Python packages. Reinstall IPM to repair the installation." To repair an affected instance, reinstall IPM.

If IRIS runs as a dedicated service account, files created in mgr/python by another account (for example with a manual irispip install) may still be unreadable to IRIS. Reset them from an elevated command prompt:

icacls "<iris>\mgr\python\*" /reset /T /C /Q