"value does not match" in Media Galley when using "/" in image Title

When i use “/” in the Titel of a Image it gives me the “value does not match”
can i recover it some how, i have edited out the “/” after but it dosent fix the Error.
i know it interacts with the code in some way and i dont have a lot of expirience with code.

HTML “/” denotes a new directory. Do not use those in file naming or there will be confusion and image corruption.