IT wonks: Upgrading to Win7 from XP - how long to incubate?

Say you were a financial organization of 500-1000 people and had legacy apps with your staff running WinXP + IE6/7. You need to upgrade to XP because security updates are ending for long-term support.

How much time would you give to planning, testing all your old-ass financial apps upon which millions of people’s dollars lie and all the web-based public-facing websites/apps you have before you top it off by rolling it to your staff?

You think it might be a good idea to involve the other departments like finance, HR, programmers on the custom-coded apps beforehand to allotting enough finances and manpower to testing and mitigating issues, before last year with this as a big project for this year?

Or would you not involve them until your formal project starts and you haven’t even started with a limited pilot group of testers running it as their primary desktop yet 1.5-2 months into your 6 month period? With your management’s internal politicking fearful of all the questions that might be posed by people seeing it installed as part of testers’ machines? So much so that they want you to install polarized anti-glare screens to block people from seeing the screens? How dysfunctional is that?

Would you say 6 months total from start to end and about just “hoping” no training would be needed based on people’s “home exposure” to Win7/Vista? We classroom-trained for Office 2010 (from 2003) and they’re hoping the intro to the Ribbon there is “enough.”

How do other places do it?

If my experience with large institutions (a large financial organization with ~1200 local employees owned by a top-5 national bank + a very large state university with 30K students and 8K staff) is anything to go by, your transition sounds surprisingly smooth, well-planned, and agreeable.

I am not being sarcastic. The financial company literally moves through more than a billion transactions a year. If the world doesn’t come to a grinding halt on migration day, I will shit a brick.

Just know that you can’t do an upgrade in place, you’ll have to do a clean windows 7 install and then reinstall everything and migrate the files and settings. XP to 7 is not supported…

This we know. I’m wondering if we’re less or more dysfunctional.