I rebuilt a web app to replace a version that we have been using for the last 3-4 years. We have a few thousand clients and a few hundred active users per day. The functionality is basically the same. The new version is a little bit faster with a few enhancement features and there are a lot of behind the scenes changes that the clients will never see. The UI is quite different but ultimately much easier to use and navigate. How should I go about having our clients stop using the old system and start using the new one? I am currently putting together a video that will play on the web site as well as within the app. The video will go through the pages and focus on some key changes. I was also thinking about an intro page that will display once the user logs in and explains some of the features.
Don't forget to warn them before the change. Users like to know in advance of changes especially changes that will affect the way they do business daily. You don't want to be surprised when you go in to do payroll (due that day) and find the whole interface has changed and you don't know what to do. If you can put up a training site for them to play with before the changeover, that might lessen stress as well.
Talk to some of your biggest clients if feasible and find out how it would be best to handle the rollout. YOu might find there are certain days of the month at that are bad for them to do a rollout for instance (back to my payroll example) in any even don't roll out a major change inthe last three days of the month or the first three days of the month as there are often monthly/quarterly/yearly tasks done then and try not to roll out the last working day before a holiday or the first working day after one (you did want to take the holiday too, right?)
The more SIMPLE and EASY TO READ tutorials and documentation you write the quicker the users will adapt and appreciate the new changes. A video tutorial/images are always really helpful. This is especially true for non technical users, who sometimes find written documentation/tutorial laborious and boring.
Maybe create an alert box or some sort of notification making the tutorials/documentation easy to access for the users so that they are well informed about the changes. An intro page is a good idea!!