The following is an example of an IPSec error message:

IPSEC(validat_proposal): invalid local address 192.1.1.1

ISAKMP (0:3): atts not acceptable.

Next payload is 0

ISAKMP (0:3): SA not acceptable!
What is the most common problem that this message can be attributed to?

A.
This is only an informational message, ipsec session will still succeed.

B.
Crypto access-lists are not mirrored on each side.

C.
Crypto map is applied to the wrong interface or is not applied at all.

D.
Router is missing the crypto map map-name local-address command.

Explanation:
This error message is attributed to one of these two common problems. The crypto map map-name local-address interface-id command causes the router to use an incorrect address as the identity because it forces the router to use a specified address. Crypto map is applied to the wrong interface or is not applied at all. Check the configuration in order to ensure that crypto map is applied to the correct interface.