Ntlmshared.dll file is part of NTLM Shared Functionality product developed by Microsoft® Windows® Operating System. It is responsible for Microsoft Corporation functionality. This part is required for NTLM Shared Functionality to function. If you are planning on replacing ntlmshared.dll with a new version make sure that you backup your old file. Replacing ntlmshared.dll file with a diffent version can cause NTLM Shared Functionality to malfunction.