If an older program worked on XP, it should work on Vista. However, no manufacturer is willing to guarantee that it will. Having said that, there are reports of older software that did not work on XP that are working in Vista - go figure!
After testing quite a few programs, I can now report that 99% of them install normally. Once installed they may need a little tweaking for optimal display though - either 256 colours or 640x480 display selected to enlarge the game's window, or sometimes both. How do you do that?
Once installed find the shortcut used to play the game (either on the desktop or the Start Menu). Right click on it and go to Properties at the bottom of the list. Select the Compatibility tab. Now tick 256 colours and/or 640x480 display and Run this program as an administrator at the very bottom. Based on hardware and system configuarations, it may be necessary to also select the other options starting with the word Disable, but try it without them. They normally relate to issues seeing menu items or buttons within the program. If it doesn't work the way you want it to you can always go back in and select them. Make sure you click Apply and then OK or the changes may not be saved.
But what do you do if it won't even install?
Vista has an automatic compatibility assistant but avoid using this at all costs as it can actually block a program from ever being able to work on your system. When they send a service pack to fix issues you may have had with that game (and others), you still won't be able to install it because the assistant has blocked it - not good. As an example, hundreds of pre-XP games that won't work on the original release of XP or even with Service Pack 1, work after installation of Service Pack 2. Safer to install your program in Vista using the compatibility wizard if you have to!
You can find the wizard in Start, Control Panel, Programs, Use an older program with this version of Windows. You will need the program's System Requirements to properly answer the wizard's questions.
The Compatibility Mode option is asking you which version of Windows to set it to. If your system requirements state more than one (eg Windows 95/98/Me/XP) just select the oldest possible one for best results (eg Windows 95).
Check your System Requirements to see if it states 640x480 display and/or 256 Colours, and only select these if they are stated.
It has a few more options than XP, select all 3 that start with the word Disable. These are visual/display settings specific to XP and/or Vista and do not apply to pre-Vista games.
Privilege level - you will only see this option if you are logged in as an administrator. I recommend selecting administrator level for all games as many actually need administrator privileges for successful installation and play.
Show settings for all users - this is up to you depending on how you already allow shared use of your PC.
Once you have completed the wizard you get to test it to see if it works properly. You will be given the opportunity to go back and try different settings if it doesn't. Once you are satisfied that it works properly you will never have to do anything again, it will save those settings for you.
Remember with each Service Pack release there will be changes to your system that may affect your software so that you may need to further tweak the compatibility settings.
Another piece of advice before I go - some installations take FOREVER, but they do actually finish eventually, so be very patient - go and make a cup of tea or something - and you will be rewarded 9 times out of 10.
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