If you are using Adobe Reader (previously Adobe Acrobat Reader) on a Terminal Server (especially when connected at a low colour depth, e.g. 8bit / 256 colours) you may encounter a situation where black or coloured boxes are shown over sections of text on your PDF files

There’s a few solutions to this, ranging from quick-fix for one user, to permanent fix for all users.

These instructions were written for Adobe Reader 9.31. Quick fix is applicable to at least Adobe Reader 8+. I prefer my clients use the free, lightweight Foxit Reader

Quick Fix:

1. Open Adobe Reader
2. Go to ‘Edit -> Preferences’
3. Select the ‘Page Display’ category
4. in the ‘Rendering’ section, set ‘Smooth Text:’ to ‘none’

Registry Fix:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\9.0\Originals]
“bAntialiasText”=dword:00000000

1. Copy the above to a notepad window
2. Save the file to a common location with a meaningful name, with a .reg extension (e.g. ‘adobe-reader-9-black-box-fix.reg’)
3. Have users double-click the file if they experience the issue, selecting ‘Yes’ when asked if they want the information merged in to the registry.

Group Policy Preferences

The above registry key can also be deployed using Group Policy Preferences on Windows 2008+, with XP SP3 and above clients that have the Group Policy Preferences Client Side Extensions installed. The Registry Wizard in GPP makes this easy!

Thanks to a post by TechFreak on the Acrobat User Community Forums for providing the ‘Quick Fix’