This is caused by Windows incorrectly caching AMP libraries when it shouldn't. Resolution is as follows:

  • Shut down AMP entirely. Use ampinstmgr stopall in a command prompt and then use Task Manager to kill any remaining amp.exe or ampservice.exe processes.
  • Run the original AMP installer (AMPSetup.msi) in repair mode.
  • Run ampinstmgr --nocache upgradeall in a command prompt.
  • Reboot the system - do not skip this step!