The web import window gives me a message stating Upgrade Your MasterCook. It was working fine previously. What happened?
It means you are using a free MasterCook.com account and not a paid subscription. The free account only allows you to store up to 25 recipes. If you have 25 recipes or more, you either need to purchase another Subscription to MasterCook.com or delete your recipes and cookbooks from your online Cookbooks screen here: My Cookbooks. Then that message will go away, and the web import window will work again.
When you use the web import, those recipes are automatically saved to your account at MasterCook.com. This is what allows it to work across multiple devices, so you can access your recipes from any device at any time as requested by many customers.