In fact, this dates back to ProfileUnity version 4.8 over six years ago. On a per application level, we can extract and load registry TreeвЂ™s and Sub-keys, including the values and data they hold.ДЇor many years, we have been offering enhanced simultaneous user login capabilities. We can break down and scan the user profile file by file and thus do the exact same thing with all registry related data. No longer is the NTUSER.DAT seen, treated and saved as a single file, at least not in the traditional sense like I just described. We handle the user profile in a different way. While they do a great job at hiding the вЂback-endвЂ™ complexity providing your users with a single store/interface from where they can access all their resources вЂ“ files, applications, desktops and more вЂ“ if no proper action is taken issues like вЂlast write winsвЂ™ might arise, potentially causing problems you can easily live without. So-called workspace aggregators are also becoming more popular. When using RDSH based multi-user solutions, combined with published applications, having more than one version of your user profile active at the same time isnвЂ™t that uncommon. This happens because even though the NTUSER.DAT holds individual user/application settings, in the form of HKCU registry entries, it is still seen as one single file by the Operating System, meaning the time stamps of the individual NTUSER.DAT files will be compared and the one thatвЂ™s most recent wins вЂ“ hence вЂlast write winsвЂ™. Now when session 2 ends, the NTUSER.DAT will again be copied back to the network share like before, overwriting all settings that came down with the NTUSER.DAT when session 1 ended, assuming changes to the user profile/applications were made. When session 1 ends, the NTUSER.DAT file will be copied back to the network share, while session 2 is still active. If changes are made in both sessions, letвЂ™s call them session 1 and 2, one will eventually overwrite the other. When a user has multiple sessions on multiple machines, the userвЂ™s profile will also be loaded at least twice. Since the NTUSER.DAT (almost) always changes, it will (almost) always be overwritten on logoff, as highlighted above as well.

However, the problem with the NTUSER.DAT is that it is seen and treated (by the Operating System) a single file, while it holds settings for all our individual user/application settings. Nothing is written back to the network share. When a so-called mandatory profile is used this doesnвЂ™t apply since all users will share the same NTUSER.DAT, renamed to NTUSER.MAN. Something, which under вЂnormalвЂ™ circumstances is what we want to happen, otherwise we would lose the changes made. If during the session, the user has made any changes to its profile, the existing NTUSER.DAT file will be overwritten (timestamps are compared). If we take traditional Roaming Profiles as an example, when a user logs off the NTUSER.DAT file will be copied back to a central file share, from where it was loaded, to begin with. Among other things, it will hold the usersвЂ™ personal application settings.ДЄccording to Microsoft, the NTUSER.DAT is a вЂњcentral hierarchical databaseвЂќ that contains information about the software, hardware and user profiles contained on a computer. The NTUSER.DAT contains the userвЂ™s registry settings (HKCU) which are unique for every user. Before we head over to how ProfileUnity can help, IвЂ™ll start with a brief explanation.Дuring user login, the user profile is copied down to the local machine the user is logging on to, this will include a file named NTUSER.DAT.

If you have been in IT for some time youвЂ™ve probably come across the last write winsвЂ™ вЂchallengeвЂ™ once or twice. Again, this will underline the power and flexibility that ProfileUnity brings to the table. Today IвЂ™d like to focus on a more specific, and well-known issue that has been with us for many years and does tend to cause some headaches from time to time: the last write wins. Last week I published a blog post around ProfileUnity named: The future looks bright for User Environment and WorkspaceВ Management, which, looking at the numbers was very well received вЂ“ if youвЂ™ve missed it you can find it here.

Where is ntuser dat