Why doesn't this work?

[Guest]

nconvert -o tiles.gif -out gif tiles.png

I get the error message

"Error: This picture cannot be written using this format (tiles.gif)"

[xnview]

nconvert -o tiles.gif -out gif tiles.png

I get the error message

"Error: This picture cannot be written using this format (tiles.gif)"

Perhaps because your original picture is in 24bits, so use -colors 256

[Guest]

Thanks mate that's worked a treat!

Much appreciated.