Reply: If it works before, it means your installation program is complete and correct. After a period time it doesn’t work normally, which should be caused by the following problems:

You need to carefully recall what has been done with the computer recently.

1. What new software was recently installed, causing some compatibility issues and conflicting with already installed software?
2. Have you deleted some files recently?
3. Has the system been shut down abnormally recently, resulting in file loss?
4. Is there any abnormality in the system? If yes, it may be infected by a virus.

Reply: Many people have encountered this problem. Here is the solution:

First you have to confirm if Visual C++ 2010 SP1 Redistributable Package x86 or x64 is installed.

VC10 SP1 vcredist_x86.exe 32 bits :
http://www.microsoft.com/download/en/details.aspx?id=8328

VC10 SP1 vcredist_x64.exe 64 bits :
http://www.microsoft.com/download/en/details.aspx?id=13523

If it is not installed, please install it first, and then confirm that the security update (KB2565063) of Microsoft Visual C++ 2010 Service Pack 1 Redistributable Package is not installed. If it is installed, please uninstall it. Then restart your machine and WAMP.