configuration process runs every time start Word 2007

I am using Windows Vista and am running Office home and student 2007 on it, for the past couple of weeks and when I open Word 2007, then I will get a message that says "Microsoft Office Home and Student 2007 Configuration Process" that begins as though just installing for the first time. The window pops up, green status bar that usually runs for a few minutes and then a popup box appears with "system must be re-booted". When I am trying to cancel the process, then it will hang for a while and then it will notify me again that a system restart is required and so when I restart the machine and again start Word again, then the same things occur again without change. When I cancel out all the windows that pop up, after sometime, Word can be used again. I dont know why this is happening but if anyone can help me out to solve this issue, then it would be appreciated. Thanks.

At the time you installed Microsoft Office, then have you tried to choose Run from Disc or install on hard drive options?

I selected the option to run from disc, thanks for the reply.

You should try to install on hard drive and not run it from the disc, since you will have this problem if you select the Run from Disc installation.