Error message when using supporter plugin

I have attached a pic of an error message that came up on screen while extending a blogs supporter status If you look at the file you'll see it referneces Custompress and Headway-photo-gallery-leaf.
I have previousely deleted both of these plugins due to conflicts/error messages etc.
The changes I was making when the error message appeared happened as expected(except for the error messages.
Any tips on how I correct this so the error messages go away(fixed)?

The reason I deleted custom press is that I wasn't using it and the headway-photot-gallery-leaf plugin is not multisite compatable.