Anybody figure this out? The key that I've generated from Mandrill is 236 characters. I've pasted it in with quotes around it. Seems to not be validating though.
I had the same issue following https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-dkim-with-postfix-on-debian-wheezy
There were new lines in the key, they had to be removed. Also, one of the new lines had a backslash before it which was treated as new line by digitalocean. The key was 238 characters long and fit alright, so those who have longer keys might try following instruction I followed or remove extra stuff - only the data between quotes should go into the field + new lines and extra quotes should be removed. Example
mail._domainkey IN TXT "v=DKIM1; k=rsa; " "p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC5N3lnvvrYgPCRSoqn+awTpE+iGYcKBPpo8HHbcFfCIIV10Hwo4PhCoGZSaKVHOjDm4yefKXhQjM7iKzEPuBatE7\
O47hAx1CJpNuIdLxhILSbEmbMxJrJAG0HZVn8z6EAoOHZNaPHmK2h4UUrjOG8zA5BHfzJf7tGwI+K619fFUwIDAQAB" ; ----- DKIM key mail for example.com
TXT field should have the following:
"v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC5N3lnvvrYgPCRSoqn+awTpE+iGYcKBPpo8HHbcFfCIIV10Hwo4PhCoGZSaKVHOjDm4yefKXhQjM7iKzEPuBatE7O47hAx1CJpNuIdLxhILSbEmbMxJrJAG0HZVn8z6EAoOHZNaPHmK2h4UUrjOG8zA5BHfzJf7tGwI+K619fFUwIDAQAB"