I would like to try this solution ...
The solution you refer to is intended to correct the permissions fault that arises for many users who go though the defragmentation procedure detailed earlier in the thread or encounter error 0x800C0155 for other reasons. Are you seeing this error?
I don't know how to ... "log on to Windows with an administrator account."
If there is only one Windows user account on the computer, it will normally be an administrator account. Click on the start button and then on your profile image (it may be the generic one  ) and select Change account settings. The type of account (Administrator or Standard user) will be shown underneath the image on the settings page.