Problem with category image

[Tikkiro]

I've searched for some help with this but couldn't find anything under the phrases I was trying so apologies if this has in some way been dealt with before.

I have a VM shop which was "migrated" over from 1.1.9 in Joomla 1.5 through to currently 2.0.4 in Joomla 2.5.6.   But it would appear that there may be some problems inherent with that migration that are now causing issues with those aspects of the shop needing changed.

I have 4 product categories each with an image but on trying to change one of these images I'm continually running into an issue that I've not managed to resolve.

If I remove the current image and try to upload a new one it either appears to have uploaded something in that I get an image holder box but no image.  I then tried uploading the image to the folder and getting it through a search instead, but that just throws up a ""noimagefound"image"  error. 

The current images all have numbers attached e.g.  Membership_4a60834e921a2.jpg  which is partly what seems to be stopping the new one from being found, as it's purely called Membership.jpg.  And if I do the "space" search it only brings up images that have the numbers - no others.

I've tried all sorts of ways to get it to put the new image in, all to no avail, so wondering if anyone here has any better ideas or can point me to what else I could try?

Oh & on another note - something maybe totally unconnected.  It did once throw up this error:

        vmError: COM_VIRTUEMART_MEDIA_IS_DOUBLED_IN_DB

but on checking, what I found was that both the old & the new VM keys are in residence i.e those that begin with "vm_" and those that begin with "virtuemart_".  Can I remove the "vm" ones or will that maybe cause bigger problems?