Error 1935 - An error occured during the installation assembly

[_Ismael_Dieppa_]

Every time I try to download Acrobat Reader 8.1.2 I get the following error message: Error 1935 - An error occured during the installation assembly. I have Microsoft Vista - Internet Explorer 7. I have a Dell computer.

[Blu12]

Error 1935 on Vista usually means a needed Windows component (often .NET or Windows Installer) isn’t properly registered or is missing an update. Try the following, in order, to clear it up:

1. Install Vista Service Pack 1 (or SP 2) and latest Windows Updates

   • Go to Start → Control Panel → Windows Update and install any pending updates.

   • If you haven’t already installed Vista SP 1 (or SP 2), download it from Microsoft (for Vista SP 1:  and install it.

   • Reboot after updates finish.

2. Download and install the full (offline) Acrobat Reader 8.1.2 installer

   • Rather than using the web-installer, grab the complete Reader 8.1.2 MSI from Adobe:

     • Go to Adobe’s archive page:
       https://www.adobe.com/support/techdocs/328450.html#acrobat

     • Under “Acrobat Reader 8.1.2,” download the Windows offline installer (usually named AdbeRdr812_en_US.exe).

   • Save it to your desktop.

   • Right-click that file and choose Run as administrator.

3. Temporarily disable any antivirus or firewall software

   • Many security suites hook into the installation engine and can block the assembly files that Reader needs.

   • Right-click your antivirus icon in the system tray and choose “Disable until reboot” (or similar).

   • If you have Windows Firewall or a third-party firewall, open its settings and temporarily turn it off.

4. Repair or update the Microsoft .NET Framework
   Acrobat Reader 8.1.2 installers sometimes need .NET 2.0/3.0 files.

   • In Control Panel → Programs and Features, look for any entries named “Microsoft .NET Framework 2.0” or “Microsoft .NET Framework 3.0.”

     • If you see one listed, select it and choose Repair (or Uninstall → then reinstall from Microsoft).

   • If none are installed, download and install both:

     1. .NET Framework 2.0 Service Pack 2 (or 3.5 SP 1, which includes 2.0/3.0):
        
        

     2. .NET Framework 3.0 Service Pack 2 (if you specifically need it):
        
        

   • Reboot once each .NET install/repair completes.

5. Re-register Windows Installer and clear the Temp folder

   1. Click Start, type cmd in the search box, then right-click cmd.exe → Run as administrator.

   2. In the elevated command prompt, type:

      msiexec /unregister msiexec /regserver

      Press Enter after each.

   3. Still in that elevated prompt, run:

      sfc /scannow

      This will verify and fix any missing system files. Let it finish (it can take 10–15 minutes).

   4. Press Win+R, type %temp% and press Enter. Select everything in that Temp folder and delete it (skip any files in use).

6. Use the Adobe Reader and Acrobat Cleaner Tool

   • If you’ve ever tried to install Reader before and it failed, leftover registry entries or partial files can block a fresh install.

   • Download the Adobe Reader Cleaner Tool from:
     https://www.adobe.com/support/contact/cscleanertool.html

   • Run it (again, “Run as administrator”) and let it remove any traces of Acrobat Reader 8.x.

   • Reboot one more time.

7. Run the offline installer again as Administrator

   • Right-click on AdbeRdr812_en_US.exe → Run as administrator

   • Follow the prompts. You should no longer see Error 1935.

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If it still fails:

• Check Event Viewer for more details

  1. Press Win+X (or Start → right-click Computer → Manage) → Event Viewer.

  2. Expand Windows Logs → Application.

  3. Look for any Error entries at the time you attempted the install—especially .NET or MsiInstaller events. That will often tell you exactly which DLL Wholesale Jewelry or assembly failed to install.

• Manually update Microsoft Visual C++ redistributables

  • Sometimes Error 1935 points at a missing or corrupted VC++ runtime.

  • Download and install the Visual C++ 2005 Redistributable SP1:
    
    

  • Also install the Visual C++ 2008 Redistributable if needed:
    
    

  • Reboot and retry.

• Try installing a newer version of Acrobat Reader

  • Reader 8.1.2 is very old. If you don’t have a strict requirement for 8.1.2, go to https://get.adobe.com/reader/ and download the latest Reader DC for Vista. It’s more compatible with updated Windows components.