So the hard drive in the Compaq was replaced with a new one correct? If so you now need to install the programs you need or had before onto this new hard drive.

Your son then wisely used the old hard drive in an external drive which you can plug into any PC computer, the make does not matter. However you cannot use the programs on that hard drive any more because too many files are now missing.

When we install a program there are files placed in different parts of the computer other than the folder set up for that particular program, these are now not available where they should be.

I hope that makes sense to you.

owbist thanks for the info DS is sotired of my computer !!! He's gone homenow but it makes sense I I really miss my little programs THANKS

I'd advise against buying a PC at a yardsale or from any private party. You have no idea what you're getting yourself into and they're often infected and otherwise messed up.

Walmart has refurbished brand name desktops for +/- $150. It's hard to do much better than to buy a reliable and reputable machine from a reputable seller for a price like that.

Programs are really best run when properly installed on a machine's internal C drive. Can't the programs you have be so installed?

If you buy a used computer its always best to do a clean install of the OS and then reload what programs you want to run... You can still run some of the programs from your old hard drive by opening the folder of the program and clicking to run its executable file (.exe). Some will work, some won't, but none will continue to have an icon on your desktop unless and until you create a shortcut for it. .. I work with computers ALL the time. When you install a program it puts files in unseen folders as well as its main folder within Programs. It also puts certain information into bios and its from there that the program told to load and be prepared to launch.