How do I copy preinstalled software to another machine?

First, the legalities. You should check the license you agreed to when you purchased the machine for the software in question. The license may restrict you from legally copying that software to any other machine - ever. (Unlikely, but it happens.) You may be ok copying it to another machine if you delete it from the first. Or you may be allowed to copy it to all the machines you own. It depends. This article goes into it all in a little more details: Can I transfer my software to my new machine?

With that out of the way, and assuming you're playing by the rules, we can move on to mechanics.

Obviously, the simplest solution is to use the original installation media and setup program. I know you indicated that you didn't have this, but I want to reiterate how important this is for other readers, and for your own experiences in the future. If you have the CD, you just install it and you're done.

If you don't have the original media, the next thing I would do is search the internet for a legal download. I would not trust sites that offer buckets of obviously copied software - besides being illegal, they're often riddled with spyware and viruses. Where I would look is on the original software vendor's website. A Google search for the specific software and version is also an approach, but again, be very very wary of illegal download sites - you can cause yourself much more trouble than it's worth, in my opinion.

It might be well worth the money to repurchase the software. Particularly for older versions, eBay, if used carefully to avoid software pirates, can be a great place to pick up what you need for not a lot of money - quite often a lot less than your own time and frustration might be worth. I did this recently myself when looking for an older version of a particular graphics editing program. Just make sure to select sellers with a stellar rating and you should be in great shape.

If it's not available in other ways, or it's just too cost prohibitive to repurchase, then there's one more step that I'll recommend trying: a direct copy.

Say the program you're wanting to copy is called "Foo", and it's installed into "C:\Program Files\Foo". Then:

• Copy the entire directory tree "C:\Program Files\Foo" from the old machine to the new. Within that directory you'll probably find the program, perhaps "Foo.exe" in our example - try running that. There's a small chance that this is enough.

• Fairly geeky: If that didn't work, look for "Foo" subdirectories underneath "C:\Documents and Setting", in particular those underneath "Application Data" subdirectories. Copy the entire directory tree(s) you find for "Foo" into an equivalent location on your new machine. There's a tiny chance this will help.

• Uber geeky and downright dangerous: search the registry for "Foo" entries, and move them to your new machine. I'm not going to go into a lot of detail here, because this is not for the faint of heart. Not only are there typically lots of entries to be copied, it's also very easy to get it wrong and damage your system. Folks who are able to do this safely already understand how. There's a small chance this could work, and a moderate chance you could harm your system attempting to do it.

Even after all that, and even in the best of circumstances, it's still possible that your program won't run. It's missing installation program could be making required changes elsewhere in the system that we simply have no way of knowing about.

Some programs are just copy-and-run. We love 'em because there is no installation program, and things just work. However the majority of significant software for Windows these days includes significant information in the registry, as well as a fair amount of file and directory setup. For these programs, there's really no practical alternative to their setup program.