A reader asks an interesting question about Windows apps and the compatibility issues that come along with upgrades:
I have a Windows XP Home Edition machine on which I have installed and used several Windows 98 programs with which I am perfectly happy and do not want to pay to upgrade … Will these Windows 98 programs work if I upgrade to Windows 7 Pro with Virtual PC and XP mode added?
The full message contains a list of programs: Mathematica, AutoCAD LT 98, and Adobe Illustrator 8, among others. Those are indeed some seriously ancient apps. Adobe Illustrator 8, for examp,le was released in 1998 (and was apparently code-named Elvis, for those who pay attention to such things).
Unless there’s an absolutely compelling business reason, I don’t recommend keeping any software around for that long. Upgrades typically involve bug fixes, support for newer hardware devices, and security issues. All of those things are worth paying for, in my opinion. And in many of these cases there are modern alternatives that are free or cheap and will open files created with the old program. The alternativeto.net web site is a good starting point for this kind of search. Here’s a list of alternatives to Adobe Illustrator, for example, and another list of AutoCAD replacements.
If you’re hoping to install older programs on Windows 7, you’ll have to check each one individually. Some will work, some won’t. Microsoft has an official Windows 7 compatibility list, which is targeted toward IT professionals. It’s a good starting point, but for any critical application you should also check with the developer of the application to see whether there are any known issues or mandatory patches/upgrades.
The most interesting part of this question involves Windows XP Mode, which is available as a feature of Windows 7 Professional, Ultimate, and Enterprise. In general, if a program will install and run on Windows XP, it should work in XP Mode in Windows 7. The big sticking point here involves any hardware requirements. You can only connect to USB devices from a virtual machine, which makes it difficult to output CAD drawings to a device that connects to a serial port. And if this version of AutoCAD requires a dongle as part of its copy protection, I’m not certain whether it will work.
The bottom line? General guidelines for app compatibility are a good starting point, but the only way to know the answer for certain is to test.
Ed Bott (@ wordpress.com) 
Ed, I have the same dilemma as your reader but for a K-12 school district. We will be installing our first Win7 boxes this summer and have the added “wrinkle” of using N-Computing devices on quite a few of them. My client suggested yesterday that I try XP mode on an N-Computing setup. I have my doubts that I can make this work. I’ll look at the sites you mentioned – I hope they list education apps as well as personal/enterprise ones.
I haven’t found any old (major) programs that don’t work, or if I have, I’ve found replacements. I have scrapped my C:\BIN directory of tools (I probably should see which ones work, and which ones don’t) which are all 16 bit as far as I know. The only ones that I find WON’T work in my BIN32 are the BASIC compilers and interpreters. Because I’m running 64-bit. I think. Bummer for me. I ended up writing what I had in BASIC into Powershell, which actually works even better (and faster) than it used to. I’ve probably got some CMD programs that would run faster if turned into Powershell too.
The only other issue has been my Palm TX, of which Palm not supporting 64-bit is a well known problem. Luckily, BlueTooth is a working option for that, if not slow and tedious.
I’ve been thinking about running a 32-bit VM (Yeah, I know NOT Virtual PC) and seeing if those issues go away. I should put that on a Todo list and see if I actually get to it instead of just thinking about it.
Hi,
i think there is a problem with your answer, because if the user run the old app with Compatibility mode i am not sure that they would work the same with XP mode on WIN7.
Hanan,
XP Mode in Windows 7 is not compatibility mode. It is a virtual copy of Windows XP running in a virtual machine. Except for the direct links to graphics and other system-level hardware, it is identical to a copy of Windows XP running on a physical PC.
I would have to say there would be no problems at all running old apps under Windows 7 using the Virtual Machine.
Don’t forget… you don’t have to run XP mode as a virtual machine. You can actually reboot into XP mode, which pretty much takes out the virtualization part. So for any app that might not work in the virtual machine, just reboot in to XP and it should work fine.
No, Charles, that is not correct. You cannot “actually reboot into XP Mode.” XP Mode is a virtual machine, by definition, a licensed copy of Windows XP supplied by Microsoft to licensed users of Windows 7 Professional/Ultimate/Enterprise. You are describing a dual-boot configuration, where you have to supply your own copy of XP. And if you want to run a program that is incompatible with Windows 7 (like a 16-bit program, which will not run on Windows 7 x64), you have to shut down all your programs, restart, run the XCP program, quit it, and then restart. A hassle.