I have an,

ip nat inside source static tcp inside_address 22 outside_address 22 extendable

Command in my router configuration that I cannot delete with the "no" version of the command. The only odd thing about the situation is the outside_address has a typo that results in the address being the broadcast address for the subnet. Until I can wipe the whole configuration after hours later today, any suggestions for deleting this are welcome...

Resolution: issued "reload" command followed by bad statement's "no" version once router came back up.

The other option would have been to administratively down the external interface. I have run into this situation before, if it's live, reload is the fastest option.

The other option ... administratively down the external interface...

Good to know. Thanks for the tip.