It may sound questionable from a security point of view, but it all depends on what the user will have access to. I met this need several times in the professional setting, with for example the setting up of posts or terminals in "self service" ...
Microsoft has thought about this need by providing Windows with the "AutoLogon" feature, but the firm does not put a tool available to activate it. Many publishers therefore offer tools that allow it. One example is Sysinternals (a company bought by Microsoft and which distributes free of charge fantastic tools), but it has not been updated to incorporate changes to recent versions of Windows. In other words, it does not work properly from Vista.... More Info »
There are also some tools that implement the AutoLogon's insecure method; I advise against it because a simple REGEDIT is then enough to recover the password in clear.
I propose to you my tool of activation of the AutoLogon, easy to use, portable (nevertheless requires the presence of the .Net Framework 4) and secured since the password of logon is not accessible in the registry... Once the functionality is installed, you will no longer need it, except to deactivate if necessary.
With the latest version, the tool can also be used in command line mode (run DipiAutologon.exe /? to obtain syntax) and is available in French AND English.