Issue
Lightroom crashes at launch in Windows, with the following error data:
Faulting application name: lightroom.exe, version: 6.2.1.10, time stamp: 0x561477b9
Faulting module name: MSVCR120.dll, version: 12.0.21005.1, time stamp: 0x524f83ff
Exception code: 0xc0000409
This can occur when the Microsoft Visual C++ 2012 Redistributable (x64) runtime has not been updated when Lightroom was updated.
Solution
Update the Microsoft Visual C++ Redistributable 2012.
From Microsoft:
"This error appears when you want to run a software which requires the Microsoft Visual C++ Redistributable 2012. The redistributable can easily be downloaded on the Microsoft website as x86 or x64 edition. Depending on the software you want to install, you need to install either the 32 bit or the 64-bit version."
Note: for this Lightroom issue, just install the 64-bit version.
See the following link: Download Visual C++ Redistributable for Visual Studio 2012 Update 4