Maybe these are silly questions, but ...
Is your system state ok?
Is Windows ok?
Are you using a 80 pin cable? If you are using a 80 pin cable then your drive should work in UDMA4 (check this in Control Panel->System->Device Manager->IDE/ATA ATAPI Controllers-> Primary or Secondary and then Check Advanced Properties)
Your H42L MUST use a 80 pin cable. If you hava one check it not have some problems. Maybe You should buy another 80 pin cable.
If the problem persists try to install your H42L in another PC. Maybe this is a drive issue, but not sure.