If you receive a message that the system has “Failed to find [name of any item] in the database” every time you try to wear or remove something:
Explanation: This error happens when the broken link gets “stuck” in the folder for some reason. When the viewer tries to update the Current Outfit folder – which happens whenever you wear or remove a body part or clothing item – it detects the link in there and thinks you want to be wearing that item. So it tries to put it on you, but it can't because the link is broken, and the “Failed” message pops up.
If that doesn't help, then make a temporary folder in your inventory. In it, put a copy of a skin, shape, hair base, eyes - nothing else - and not the ones you are already wearing. Then right-click the folder name, replace outfit (not add or wear). Then check Current Outfit folder (not Worn tab) and delete any links showing as not worn. Then relog. (Please follow these steps exactly as given - it matters.)