Changing the CommandTimeout in SQL Management studio

Changing Command Execute Timeout in Management Studio:

Click on Tools -> Options

Select Query Execution from tree on left side and enter command timeout in "Execute Timeout" control.

Changing Command Timeout in Server:

In the object browser tree right click on the server which give you timeout and select "Properties" from context menu.

Now in "Server Properties -....." dialog click on "Connections" page in "Select a Page" list (on left side). On the right side you will get property

Remote query timeout (in seconds, 0 = no timeout):
[up/down control]

you can set the value in up/down control.

Right click in the query pane, select Query Options... and in the Execution->General section (the default when you first open it) there is an Execution time-out setting.

While on the table designer, you get error : "Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding."

Remove check box under : Tools --> Options --> Designers --> Table and Database Designers --> Override connection string time-out value for table designer updates

Then timeout, refers to "connection string execution timeout"

So if you uncheck it, you have to close ssms and launch it again

When reopening, at "connect to server" dialouge, before connecting, press options button, go to "connection properties" tab, and make sure "execution time-out" value set to zero (it means unlimited)