If you have updated Windows 11 to 24H2 and Acrobat/Reader is not starting please refer to this page 

Please run this uninstall tool:

http://plugin.fileopen.com/tools/FileOpenUninstallTool.exe

Then try again using this installer: http://plugin.fileopen.com/current/FileOpenInstaller.exe

Be sure to download the installer before running it. That is, when you have a choice between Run and Save, choose Save. Make sure to have all web browsers and Adobe products closed when running the installer. If the installer says that the system must be restarted then please be sure to reboot your computer. After you have installed the plug-in please try to open the following PDF:

installcomplete.pdf.

These error messages are displayed when a companion process, FileOpenBroker64.exe, is not running. What we want to do is get the broker process running again.

• If you have been able to view protected documents until recently, then the broker process was running and has stopped for some reason. The easiest way to get the broker process running again is to simply reboot. If a reboot does not solve the problem, please request technical support.
  
  
• If you just installed the FileOpen client plug-in and this is your first time trying to open a protected file, then you need to get the FileOpenBroker64.exe running. You will also want the FileOpenBroker64.exe to start every time you log in to the machine. To do this you can create a shortcut to
  
  C:\ProgramFiles\FileOpen\Services\FileOpenBroker64.exe
  
  via
  
  C:\Users\YOUR USERNAME\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup
  
  for launching the FileOpenBroker64.exe at login time. After creating the shortcut you can start FileOpenBroker64.exe manually by double-clicking either on the original .exe file or the shortcut. Once you have verified that the FileOpenBroker64.exe is running as a process in your Task Manager, you should be able to open protected documents for which you have permission. If you encounter this error on a server environment (e.g. Citrix or Terminal Server) please review the guidelines for using the plug-in in server environments.
  
  
  

You cannot view FileOpen protected documents in the Chrome browser, but you can change Chrome's settings so that you open PDF documents in Adobe Acrobat / Reader.

You can set this up by following the instructions below:

1. Open Google Chrome.
   
   
2. Type: 'chrome://settings/content' into the URL bar.
   
3. A 'Content Settings' box will appear.
   
   
4. Scroll to the bottom of the 'Content Settings' box and select 'Open PDF files in the default PDF viewer application' option.
   
   
5. Click on the 'Done' button in the bottom right corner of the 'Content Settings Box'.

**Note: This will open documents in your default PDF viewer application. So you will need Adobe Acrobat / Reader, Bluebeam or Foxit set as your default PDF viewer in order for this setup to work properly with FileOpen protected documents.