SQL Server 2008 database engine login failed for administrator user in windows 7/8

I am administrator in my machine windows 8, But I cannot login to SQL using my administrator user.
Problem I installed SQL using other user and I didn't remember its password to solve this problem I followed the following steps:

1. Open the command prompt (Right-Click on and select "Run As Administrator")
2. From the command prompt type net stop MSSQLSERVER
3. Next type net start MSSQLSERVER /m
4. Open SQL Server Management Studio. Do not login, cancel the login dialog.
5. From the file Menu select New->Database engine query, and login (Make sure you use the host name and not localhost).
6. Execute the query ALTER LOGIN sa WITH PASSWORD = ''; to reset the password (if the sa is not enabled then type ALTER LOGIN sa ENABLE to do so)
7. Login with the sa user and add the Administrator user.

Failed to install Lync in Windows 8

When tried to install Lync in Windows 8 I faced error Another Installation Already in Progress (Although I didn't run previous installation). After some investigation I discovered I need to call setup as administrator.

But in Windows 8, right-clicking on a program in the Start screen won’t display Run as administrator option. While Run as administrator option is available when you right-click on a program shortcut on the desktop, the same option doesn’t appear when you right-click on program shortcut in the Start screen.

Step 1: Switch to the Metro Start screen and start typing the program’s name to see your program

Step 2: Right-click on the program name to see Advanced option.
Step 3: Click on Advanced and then select Run as administrator option.
After these steps, I can install Lync