A much touted feature of Windows Vista is the new User Account Control. This feature, enabled by default, in Windows Vista causes programs to run in a "limited" user account thus preventing them from making system wide changes. This feature is beneficial because a program that is malicious will not be able to install itself on your computer without first requesting administrative permissions from the user.

However, UAC has proven to also be a very problematic new feature as software vendors struggle to design their software around it. If you are having trouble running a certain program on your computer, try running it with elevated permissions. Right-click the file and select "Run As Administrator." This will give the program administrative permissions on your computer and could resolve issues that you are having. If it does, you can configure the program to always run as administrator. This can be done by modifying the file's properties (right-click the file, click properties).

Please read this technet article for information about working with UAC: http://technet.microsoft.com/en-us/library/cc709691.aspx

It is interesting to note some of the peculiararities of UAC when you run a program "as administrator." Windows is designed to have several user accounts. You may have an account for your children, an account for your spouse, and an account for yourself so that all settings and documents can be kept seperate. If you login to one account, all the settings and documents are different than when you log into another account. The same is true with UAC. When a program is run as "Administrator" the program takes on all the properties of the built in Administrator account, and no longer uses the settings of your own account. This means that any customizations, such as network file shares that are specific to your user account, will not be available once the program is run as administrator because it is being run in an entirely different user account. So, if you run a program as administrator, and suddenly it appears that all your customizations in the program are gone, you'll know why. It will need to be reconfigured while it is running under the administrator account.