I tried to make a login tab in my VI, but it doesn't seem to work quite as I expected. What I tried to do is to make a tab control with the first tab being login-window. When the user writes in a username and password that matches the one from the text file, the user unblocks the next tabs. The problem I experience is that the username and password I write in the strings are not read and the returned string is empty. Also, I can't figure out how to make the other tabs "blocked" for access during the login session... Any ideas?