A forum member told me that it could be a trojan suggest me to post in this section becuase BTC client does not use VC in any way.
The official Bitcoin Windows binary isn't built with VC, but it does use the Microsoft Visual C++ Runtime (msvcrt.dll).
This file might be corrupt. You can try running "sfc /scannow" from an administrator command prompt. This will attempt to find and repair bad system files.