I have a HP Pavillion that came with Vista Home Basic already installed . What I would like to know is can XP Professional be installed on the same computer with both OS being operative at the same time successfully My situation is that I manage to find a lot of freeware/open source that supports XP but it's rare for me to find specifics that is supported by Vista (or at least: that's what I read in a lot of freeware/open source descriptions) . Also, I've read in some previous posts here that one could change some 'executables' of the XP software and/or install using Vista's compatibility mode . I've already tried playing with the different features of the compatibility mode and have had no further progress with the XP software . Could you give me more information on what the 'executables' of a particular software is all about if possible so that I may have another option when going at it again I'd really appreciate any information that can be offered .

What program are you having problems with?

You can have both XP and Vista installed side by side but you need to install them in a chronological order, i.e. XP first and then install Vista on top of it.

The executable is the file with the .exe extension and is the one you run to start the program.

In general, if a program is to work in compatibility mode, you'll have to run the installer in compatibility mode (both as XP SP2 and as an Administrator). Then, once it's installed, you'll have to find the program's directory in the Program Files folder - and set each file that ends in .exe to run in compatibility mode.

This presumes that the program makes no calls to restricted areas of the OS (both file system and registry) when it's not elevated (remember that Vista will act as a Standard User unless it's specifically told to elevate).

This also presumes that the program doesn't call on other executables that aren't specifically set to run elevated. Finally, even if you do get it to work, you may find that some of the programs only work part of the time. For example, pcAnywhere v11.5 works just fine under Vista - until you try and schedule something. Then it balks and won't run.

You can install XP on your Vista system if you have enough free hard drive space to make another partition for it. Then you'll have to buy a copy of XP and then try and locate XP drivers for all of the hardware devices that you use. Also, you'll have to muck around in the boot manager to make sure that you've got the option to boot to each OS.

Another option is to use a Virtual Machine to install XP into - that way you won't have to reboot to get to XP. But you'll need more memory to do it (Home Basic computers don't usually come with a lot of RAM).