Thanks @sawa and @ranlo! I manually downloaded the receiver_69.csv into .devcoin/receiver/ then started devcoind, now we got the explorer back online:
http://explorer.devcoin.info/I had this issue before, somehow devcoind marked receiver_69.csv as downloaded but the file was missing, it is not downloading the file again so the program just ends with an error.
Now we have to get back into an exchange because Coingather delisted Devcoin

. I had around 25 million coins there to help with market-making.