Someone registered to my paid forum and they never paid their invoice. I have deleted their id  and was left with the invoice as a result. When I saw expired invoice assigned to the guest I wanted to deleted it. It gave me an error and now I am getting the heading " A configuration or server error has occurred" and below "EX0 -something went wrong, Please try again." when going into to the "invoices" section in commerce. 

I opened up a ticket for it, as I found no post with similar issue. I guess the learning was to delete the invoice first and then the id. I think. Nevertheless executing "delete" button should not cause configuration issue. This is of course a bug and they need to fix this globally. 

Be aware 

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