I cannot seem to launch and run 64 bit apps on my Windows 7.  I always get the same error 
"The application was unable to start correctly (0xc000007b). Click OK to close the application."  Please help .. what am I missing all of a sudden?  I have a Dell N5050 with Windows 7 home premium that was installed when I purchased it, service pack 1.  

Please run a system file check (SFC) & DISM if you are on win 8 or higher
All instructions are in our Wiki article below...
Should you have any questions please ask us.

System file check (SFC) Scan and Repair System Files

Hi ckeel01,

The application was unable to start correctly (0xc000007b), this error may occur because of the dll files used by 64 bit applications is mismatched with those for 32 bit.

We may take use of Process Monitor to look for the related DLL files, then copy the good one from a working OS which has the same OS version.

If there is no working machine available, we may first take a try with the SFC /scannow command, if that also won't work, please find your install media or Recovery disk to do an upgrade (in-place) install, which won't affect the files or the installed apps, and will replace the bad system files.

How to Perform an In-Place Upgrade on Windows Vista, Windows 7, Windows Server 2008 & Windows Server 2008 R2

Regards