Acrosup64.dll Is Not Marked For Installation Free -

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

Step 1: Terminate the Spooler & Locking Processes

acrosup64.dll is often loaded by the print spooler or a system tray app.

• Press Win + R, type services.msc, hit Enter.
• Find Print Spooler. Right-click → Stop.
• Open Task Manager, kill any process named CutePDF, PrimoPDF, or AcroTray.

Remediation Strategy

Level 1: Basic Repair (Success Rate: Low) Running the standard "Repair" utility from the Control Panel often fails because the installer hits the same logic error. However, it is the recommended first step. acrosup64.dll is not marked for installation

Level 2: Adobe Cleanup Tool (Success Rate: High) Adobe provides a specific tool designed to resolve this exact registry state conflict.

• Action: Download and run the Adobe AcroCleaner Tool.
• Note: This tool forcibly removes installation files and registry keys, allowing for a fresh installation.

Level 3: Microsoft Program Install and Uninstall Troubleshooter (Success Rate: Medium) Troubleshooting Guide: "acrosup64

• Action: Use the Microsoft "Program Install and Uninstall Troubleshooter." This utility fixes corrupted registry keys that might be telling the installer that acrosup64.dll is not marked for installation when it actually needs to be.

Level 4: Manual Registry Edit (Advanced)

• Search the registry for keys related to the specific patch or the DLL and remove the "Installer" keys associated with the failed update. This is risky and recommended only for IT professionals.

Preventing the Error in the Future

Once you resolve "acrosup64.dll is not marked for installation," follow these best practices to avoid recurrence: Press Win + R , type services

• Always uninstall old Adobe versions before installing new ones using the official Adobe Cleaner tool.
• Avoid manual deletion of Adobe folders—always use Windows "Add or Remove Programs."
• Keep Windows Update current to avoid MSI engine bugs.
• Do not use registry cleaners (e.g., CCleaner Registry Cleaner) on Adobe product keys—they often break the installer state.
• Create system restore points before major software installations.

Step-by-Step Solutions

Below are the most effective solutions, ranked from least to most intrusive. Always restart your computer after each major step to clear temporary locks and caches.