If you start your computer once, which is running Windows 7 hangs up at the Welcome screen continuing indefinitely, then read further, I will be able to show you how to solve this problem. There are many reasons which will lead to the unpleasant situation of your computer freezing on the Welcome screen, but the most probable reason may be a third party software and/or service that runs with Windows. In my case it had been my antivirus software, maybe an update messed it up. So so as to resolve the problem, you must find the problematic software first. Restart your computer and keep pressing F8 until you get to the Windows 7 Advanced Boot Options screen.
Then Pick one of the "safe mode" options and Enter. On the login screen enter your password and Windows will start in safe mode. Here's how I found the matter and fixed it, the procedure should fix your problem, too:
Click on the Start menu, enter "MSConfig" and press Enter
On the final tab click Selective Startup
Clear the Load Startup items checkbox
Click the Services tab, click Hide All Microsoft Services to select it then click the Disable All button
Click OK and restart your computer
