I installed MySQL 5.0 on a Windows 8 machine, everything worked out just fine, but the next day, after a reboot, the MySQL service would not start. The error message was

Could not start the MySQL service on Local Computer.
Error 1067: The process terminated unexpectedly.

I tried a bunch of things, even reinstalling MySQL, but it wouldn’t start anymore.

Looking at the error logs (in the data directory, in my case in C:\Program Files\MySQL\MySQL Server 5.0\data, the file is called server.err), I read

InnoDB: Operating system error number 87 in a file operation.

Thanks to a blog post on websofia.com, I finally managed to get the thing up and running again by adding

innodb_flush_method=normal

to my my.ini. This finally solved it. Thanks Alex!

Check the blog post as it contains some other very useful learnings when dealing with MySQL on Windows.