Previous incomplete uninstallation processes or corrupted setup packages frequently leave behind broken registry keys and orphaned files.
If you prefer not to uninstall the software, you can attempt to force the Windows Installer to reset the state of the components.
To help pinpoint the exact remedy for your system, please share a few more details:
If you've tried all the steps and the error persists, you may want to consider: acrosup64.dll is not marked for installation
: Stalled background threads block the installer package from modifying current local files.
The acrosup64.dll file manages 64-bit installer configurations. If the registry claims the file exists but the physical file is missing (or vice versa), the installer aborts with Error 2753.
Registry Path Example: HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\[Alphanumeric_ID] 👉 Check "ProductName" key value on the right windowpane. 5. Manually Deploy via Extracted MSI Packages The acrosup64
: This is a standard Windows Installer error (Internal Error 2753). It means the installer script is trying to register a file ( acrosup64.dll ) that it believes is not part of the current installation package or is already registered in a way that prevents overwriting.
The Windows Installer engine thinks the acrosup64.dll file (Acrobat 64-bit Installer Support) belongs to an active layout, but the setup script says otherwise.
: If you are deploying via GPO or SCCM, manually extract the MSI and the MSP (patch) file into a new folder. Use the command line msiexec /a [path_to_msi] /p [path_to_msp] to administrative-install the patched version into a flat folder before running the final setup. acrosup64.dll is not marked for installation
Web-based stub installers frequently trigger this error because they cannot handle corrupted target environments. Using the full offline standalone package circumvents these issues. error the file acrosup64.dll is not marked for installation
Remember to always run installers with administrator privileges, keep your security software active (except when troubleshooting), and download software only from official sources. With the comprehensive solutions outlined in this guide, you should be able to resolve the error and get back to using Adobe Acrobat Reader normally.
7-Zip or similar extraction software