Acrosup64.dll Is Not Marked For Installation May 2026

Microsoft offers a dedicated tool to fix Windows Installer corruption.

The error "acrosup64.dll is not marked for installation" is a classic example of a Windows Installer state error. While it can be frustrating, it is rarely a sign of a virus or hardware failure. In 90% of cases, using the official Adobe Acrobat Cleaner Tool to remove the corrupted install and reinstalling the software fresh will permanently resolve the issue.

Troubleshooting Guide: "acrosup64.dll is not marked for installation" Error

If you have tried all six solutions and still see the error, the issue may be deeper:

In extreme cases, a Windows repair install (keeping your files) or a clean OS reinstall may be necessary—though very rare for this specific error.

Once you resolve "acrosup64.dll is not marked for installation," follow these best practices to avoid recurrence:

This is rarely a "virus" or a "corrupt OS." It is a version mismatch and ACL (Access Control List) conflict.

Here is the technical cascade:

In short: The installer sees a ghost. It knows the file should be there, but it has no instructions on what to do with it.