Well right off the bat I can think of 2 or 3 different ways to make your programs work again.
1: Is to rearrange your drives on their ide cables until you get the second harddrive to be the desired drive letter. Or
2: Go into the properties of the programs affected and change the letter they associate where to look or do it in the registry, whatever is needed. Or
3: Is to uninstall/reinstall the programs affected, pointing them to the correct drive letter. You'll probably get errors such as 'There is already a file named ***, do you want Windows to overwrite it?' Choosing yes or even no will result in the program funtioning properly but I would go for the overwrite unless there are files in them you do not want to lose.
Let us know if any of these ways work, more ideas to follow if they don't.
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