People seem rather scared of re-activating Windows, re-activating Windows is a not an issue, it's a hassle at best, but the need to re-activate doesn't jeopardized in any way your Windows installation or your files.
In relation to the cited post I don't share this person's experience in any way or form, but I can give you some advices that would prevent such situations. Because Parallels depends on how OS X works internally and how Windows works internally there are things that you just have to be careful and are beyond Parallels control.
Advices:
1.
Don't re-activate Windows immediately when it asks you to, you have three days, so there's no rush, SPECIALLY if you updated Parallels and haven't finish updating Parallels Tools (Parallels drivers for the Guest OS), only once you finish all the updating, should you re-activate.
2.
Read the manual first and proceed accordingly.
3.
Updates handling.
a. Apply/Install Mac OS X software updates first (if any).
b. Apply/Install Parallels latest versions secondly (if any).
c. Apply/Install updates to the Guest OS (Windows) Boot Camp drivers (Apple Software updates) thirdly.
d. Apply/Install Microsoft/Windows Updates to Windows (guest) fourthly.
e. Always reinstall Parallels Tools in the Guest OS when you install a new version/build
of Parallels (this is when the re-activation usually kicks in).
4.
NEVER upgrade software 'on the road' when you don't have access to original installation media and/or backups, most of the times it will work well but one out of a hundred or a thousand it won't (with any piece of software, firmware, hardware or anythingware) and you're screwed, don't do it specially if what you're running at the moment is running fine and there are no immediate dangers if you don't update.
Last edited: Jun 14, 2008