This error is typical for Windows 7 and Vista. When you turn on the PC and try to log in as an additional user (not the Administrator), the Profile Service reports that this is not possible. People create such profiles in order to lend a computer to someone from friends or family members and not to fear that they will change some settings or accidentally damage files. But then the system automatically opens exactly this profile or refuses to enter at all. Sometimes it is not possible to confirm that you are the full owner of the PC - there is simply no button with the name of the administrator. Why this happens and what can be done in a similar situation, we will describe further.

Solving login problems.

What is the error and why it occurs

This error means that the system is trying to load the "Desktop" and a set of functions for a specific user, but does not find information about what it should be. In general, the creation of additional profiles in Windows 7 and Vista is an unfinished option. Very often there are various system errors associated with the entrance. It also happens that the profile is incorrectly deleted - the data folder is missing, and the name is displayed when the OS starts. User Profile Service may prevent users from logging in for the following reasons:

1. Exhibited a team in Group policy, prohibiting entry through additional profiles.
2. Removed all profile data from the repository, and not through a special option. As a result, there is practically no profile, but there is a picture with his name on the boot screen.
3. You launched a security check using antivirus and at that time decided to change the profile to work on a PC.

Error Correction with Registry Editor

To begin with, in order to still log in, you need to reboot and click F8 several times until we are offered “Safe Mode”. Before you open the registry and change something in it, be sure to make a copy of it. Each section stores important information that you may accidentally lose by making some mistake. Therefore, first do this:

1. Click Win + R, insert “regedit” (without quotes) in the line and confirm the action.
2. In the left column of the maximized window, find “Computer” and right-click on it.
3. Select "Export" and specify a non-system disk for storage (very often it is called "Disk D").

Now, if something happens, you can easily restore the registry entries from a copy. But back to the profile service, which prevents entry:

1. In the Registry Editor (we have already opened it) on the left we are looking for the HKEY_LOCAL_MACHINE folder.
2. When we open it, we see many more folders inside, but we need Software. It also contains many sections, and we are looking for Microsoft.
3. In the Microsoft folder, we are interested in Windows NT, but this is not all - in the latter we choose CurrentVersion. And here already contains information about profiles - the ProfileList folder.
4. Now we see several sections entitled S-1-5 - we will need two of those to which many numbers are assigned.
5. Look at the characteristic of the ProfileImagePath file. In the "Value" column should be written: "With / Users / Your nickname for the profile.
6. If everything is all right and we have found the necessary section, we return to the folders with S-1-5 and numbers. At the end of one of them stands: ".bak". We remove this ending and write something else (for example, “.old”), and also look for the RefCount file, click on it twice and write “0” in the line.
7. To the second folder, simply add the .old postscript (or whatever you like).

Thus, we isolate these folders instead of deleting, because first we need to make sure that we have found the right solution to the problem, and the error no longer appears. If this does not help, you can return everything as it was.

Solve a problem with system recovery

This method is much simpler and safer than the first, but does not always give the desired result. If registry manipulations seem too complicated to you or they did not work out, go to the following method:

1. Restart the OS again and press F8, only this time we do not log in to the system, but select “Troubleshooting”.
2. A list of different approaches to the regeneration of the OS will appear here, but we need the second “System Restore”.
3. The difficulty lies in the fact that in the process you will have to remember the date when you quietly logged in under any name, and there were no problems. Indicate it when the corresponding request comes from the system.
4. Restart the OS and try logging into the profile as usual.

Other possible solutions to the problem with the Windows Profile service

You can also turn on “Safe Mode”, log in as a PC owner and create a new profile, and then return to standard mode and check if the error has disappeared. If you remember, we found in the registry a folder with the name S-1-5 and numbers: one was with the ending “.bak”, the other was without it. So, the latter may be absent. Then you don't need to rename the first one, just get rid of it.