|| I get internal server errors when I generate HTML files.
|| The most probable reason this happens is because the host/server you are using are having trouble coping with the load on building indexes from the web browser. A quick remedy for this problem would be to wait a couple of minutes and just click the back button of your browser. Building indexes from the web browser can be resource intensive as a script is executed for each page being built.
To completely solve the problem open admin3.cgi with a Unix compatible text editor like Textpad (textpad.com) and set the $build_pause = "8"; value to a higher value. For example: $build_pause = "15"; This value is the number of seconds that a pause is implemented to give the server some room to breath after each page build.
Something else to do would also be to build from Telnet/SSH. This is much lighter on server resources and anything from 100% to 1000%+ faster.