Adobe Reader stores data and settings in the Windows registry. Corruption of these registry entries results in Adobe Reader not working properly. Whether Reader doesn’t launch properly or PDF files can’t be viewed in your Web browser, a repair installation fixes the problem. You can fix Adobe Reader’s registry entries using Adobe Reader’s repair installer. If PDF files do not load in Reader because of file registry issues, you can fix the problems with Windows’ built-in file association tool. Writer Bio

How to Fix the Registry for Acrobat Reader - 21