do you really mean the names are blue rather than the folder icons?
If you do actually mean that the folder icons are blue I have to ask what add on File Manager are you using? PowerDesk by any chance? It has the ability to allow the user to change folder icons to Red, Blue, Green Cyan, Magenta, White, Black or the default tan.
If you actually mean the folder name is blue such as $NtUninstallKB2535512$ is blue or ie7 or ie8 or ie9 is blue then that is quite normal and indicates the folders and contents are compressed or encrypted.
Don't delete them. If you are running low on disk space and really need the room freed up you can delete thos with names like $NtUninstallKB2535512$ or $NtUninstallKB2544893$ or similar with the $NtUninstall at the beginning and a $ following a number at the end of the name BUT DO NOT DELETE the one named $hf_mig$.
My son recently opened up my folder views to show hidden files and folders. He then went into C:\Windows and I noticed that there were more than a few 'BLUE' folders taking up a lot of space. Is it safe to delete these blue folders or should I leave them be. There must be a reason why they are hidden, isn't there?
Would be thankful for any help with this . To delete or not to delete, that is the question?
Thank you.

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