If you've installed the Beta of VS2010 on the same box as a VS2008 install, you may have found that your VS2k8 help is now broken.

Hitherto, this hasn't been a huge problem for me, as I tend to use the online version of the help on the MSDN website (both Bing and Google are better at finding the contents I'm interested in that the built-in search facilities!)

However, I've just installed SP1 of the Surface SDK and I wanted to read up on the new LibraryContainer and its friends. The docs are published in help format, and require the help viewer to be working...

Turns out that things aren't so bad. If you fire up the Add/Remove programs applet, and Remove/Change "Microsoft Document Explorer 2008" (choosing the "Repair" option when given a chance), then it fixes it. You have to through the misery of "Help is updating to reflect your recent changes...", but then a) Help works in VS2008 and b) Help still works in VS2010!