Permissions for HKEY_CLASSES_ROOT

I was looking at the Registry and found a strange User With Full Control for HKEY_CLASSES_ROOT. See the Attached JPG file for information. When I deny Full Control to this User, the machine will boot into the Desktop Wallpaper with no Taskbar or anything else, just the Desktop wallpaper and then everything stops. Has anyone seen any thing like this? Is it a security problem?

 

It's not a security problem. It should be allowed full control, permissions for registry keys should be left alone and not be changed unless you really know what you're doing.
For permissions to registry keys, it is used to control registry key permissions for each user profile.

 

I realize that. I just have never seen a user with a name like the one shown in the attachment and I think it might be a security problem.

I have 3 computers with similar setups and the others do not have this strange number listed as shown.

Has anyone seen anything like that shown on the attachment.

 

Silver, are you using Vista? That strange user you are talking about seems to be a SID. Here's something which may be of help to you:
http://support.microsoft.com/kb/243330

 

I am using XP Pro, SP2. Thanks for your help. I looked up the article you referred me to, but there is no mention of an SID beginning with S-1-5-21....

 

http://www.microsoft.com/downloads/...76-9BB9-4126-9761-BA8011FABF38&displaylang=en
http://technet2.microsoft.com/WindowsServer/en/library/60eaf668-4001-487f-9924-e8a71dfffacc1033.mspx
http://www.windowsitpro.com/Windows/Articles/ArticleID/20046/pg/3/3.html
http://www.windowsitpro.com/Article/ArticleID/14781/faq.asp?faqnumber=1702
http://en.wikipedia.org/wiki/Windows_Server_domain

 

The theme you are using gave me the impression that you are using Vista. To simplify things, the strange user you are seeing in Permissions is a SID (security identifier).
This article explains it best:
http://en.wikipedia.org/wiki/Security_Identifier

 

I am using WindowBlinds with Vista Transformation Pack v6 which gave you the impression I was using Vista.

I guess I should not worry, although my other systems, which are configured almost the same, are on the same network, do not have an SID as a User in HKEY-CLASSES-ROOT.