Recently I tried to run Oracle SQLDeveloper but I was getting the error that msvcr100.dll missing from your system. I tried with different JDK version but in vain. This can come while installing any other software as well. To resolve this problem just download and install Microsoft Visual C++ 2010 Redistributable Package. it will solve your problem. The following are download links as per your OS.
(x64 bit) http://www.microsoft.com/download/en....aspx?id=14632
(x86 bit) http://www.microsoft.com/download/en...s.a...