How to publish multiple websites in a solution?

By default you can publish only single website at a time unless there is a dependency on other websites in a multiple websites in a solution. So if you want that along with your startup website other website should also publish then you will have to do some project dependency settings on the solution level.

Following are the steps:

1. Right click on the solution and choose Project Dependencies from the short-cut menu.
2. In the Project Dependencies window go to Dependencies tab.
3. Choose your main website(startup) from the 'Projects" dropdown.
4. Check all the other websites/web servies in the "Depends on" section that you want to publish along with your main website and click on Ok button.

Now when you publish your main website, you will be prompted with publish windows for all the depended websites for publishing.

But if you want to publish only startup website but you are prompted with other webistes/web servies publishing windows as well, which you dont want to publish then remove them from the dependency list of the startup website through above mentioned steps.