Can't delete a grey box?

I recently was trying to create a new button on my toolbars for a macro I created.
During this process a light grey box appeared which cannot be selected and you cannot
select cells behind it. This box resembles an Autoshape box that you can create, however I
can't seem to right click or left click on it. I delete the rows underneath the box but it
stays there. It only appears in one of my sheets that I had open at the time. If I copy the
sheet it will follow on to the new sheet and it also prints out with the sheet.

Any ideas on how to get rid of it? I can copy the cells and paste it to a new sheet, so this
is just a nuissance that I want to know how I created.

Naeblis