Here’s a good bug report for the issue :
The root cause boils down to Windows Installer ( msiexec.exe ) database corruption. When Adobe updates fail mid-process, or a prior version is improperly removed, orphaned entries stay behind in the system.
Manually copy acrosup64.dll from a working system into the Acrobat folder and register it with regsvr32 , but this is not a permanent fix.
7-Zip or similar extraction software
If the automated cleaner tool fails, manual intervention in the Windows Registry may be required. acrosup64.dll is not marked for installation
To fix the problem, you must remove leftover file remnants and registry keys from previous Adobe installations that block the Windows Installer from executing. This specific error occurs when upgrading, reinstalling, or deploying Adobe Acrobat or Adobe Reader . The Windows Installer engine blocks the process because it mistakenly believes a version of the 64-bit installer support library ( acrosup64.dll ) is already actively registered or conflicts with the new deployment. Why Error 2753 Happens
Attempting to install a 64-bit patch over an older 32-bit baseline installation of Adobe software.
When Windows' built-in uninstaller fails with the same error, third-party uninstallers can remove stubborn installations.
(Acrobat 64-bit Installer Support file) may be orphaned in the system folders, causing the installer to fail when trying to "mark" it for a fresh setup. Damaged Local Files : Corrupted files in the Program Files Here’s a good bug report for the issue
Corrupted or outdated registry keys point to DLL files that no longer exist or cannot be overwritten.
Ensure you select the correct architecture (64-bit is standard for modern systems, matching acrosup64.dll ).
If applicable, manually run any accompanying .msp update files located in the same directory afterward. Root Causes of the Error
If the cleaner tool misses local cache stores, local data profiles must be wiped manually to stop the installer script from referencing old component paths. Press Win + R to open the dialog box. 7-Zip or similar extraction software If the automated
The Windows Installer engine (msiexec.exe) may have pending transactions or corrupted cached data preventing new file registrations.
Even after using the cleaner tool, active user profiles might contain cached configuration profiles that disrupt new setups.
Look for keys starting with (this is a common prefix for Adobe products) and delete them if they reference Acrobat or Reader. 🖥️ Alternative: Register the Installer Service
error the file acrosup64.dll is not marked for installation