As a consequence of the deficiency in CD40 ligand, the T-lymphocytes in patients with X-linked Hyper IgM (XHIGM) are unable to instruct B-lymphocytes to switch their production of immunoglobulins from IgM to IgG, IgA and IgE.
Windows event logs are also files, but they are commonly locked by Windows (Event Log Service) and it is impossible to open these files on live system. But if the computer is started from another disk or the system drive from the analyzed machine is connected to another computer, you can read event logs as files. The default location of event logs on Vista/2008 and better is C:\Windows\System32\winevt\Logs\.
up vote 20 down vote accepted. Windows account details are stored in the SAM registry hive. It stores passwords using a one-way-hash (either LM Hash, which is old and weak, or NTLM hash which is newer and stronger.) The SAM hive file is located at %WinDir%\system32\config\sam. This directory, and it parents, are by default inaccessible to non-administrative users.