WinDirStat and System Volume Information

I have System Protection turned on on my OS drive and have about a dozen restore points available. Max space for system restore is set at 5.3GB. When I run WinDirStat it shows System Volume Information at zero for Size, Items, Files and Subdirs. What gives?

EDIT - Just ran TreeSize Free and that does show 4GB used for SVI. Both programs were run 'As Administrator'

I prefer the way WinDirStat displays the results but it looks from this that they may not always be correct.

By default the System Volume Information folder has security settings that do not permit access by any user account, including an admin account. This is to protect the important data it contains from inexperienced users. Long history has shown that users do need to be protected from themselves. They want the protection, but often without understanding the implications. By default all software a user runs inherits his rights and privileges. WinDirStat runs this way and is thus unable to read the contents of the folder and is unable to account for it's contents. Windows Explorer and similar utilities have the same issue.

TreeSize gets around this problem by using a service that runs under a system account with higher rights that can read the folder. Designing software that works this way is more complex, particularly when the security implications are considered. The developers of WinDirStat and many other similar utilities chose to do things the easy way and accept the problems.

I did say that both programs were run 'as Administrator', i.e. with elevated privileges. Seems that WinDirStat can't handle that so just runs with the user's normal privileges - Admin in this case. It undermines the usefulness of WinDirStat but can't be that difficult to implement as Ccleaner as well as Treesize manages to access SVI and even delete individual restore points, and without needing to ask for higher privileges. Anyway, why the heck does Microsoft keep using the same names to mean different things! Administrator is just one example, Outlook another. It just confuses people. <end of rant>

Even an elevated admin account has restrictions and does not have the rights to access the System Volume Information folder. An admin account can change permissions but you had better know what you are doing. TreeSize is using a service running under a system account that does not have these restrictions. CCleaner isn't accessing the folder directly but is using system provided functions designed to provide certain types of access.