Errors in a sent campaign.
WHAT YOU CANNOT DO
Recall it. A sent email is gone.
WHAT YOU CAN DO
If the link points to a page on your site, change the page rather than the link.
Create the wrong URL as a redirect to the right one. The broken link then works.
That is the single most useful recovery and it works surprisingly often.
IF THE LINK IS EXTERNAL
You cannot fix it. Send a brief correction.
SENDING A CORRECTION
Short, honest, with the correct link.
Do not over-apologise. A one-line correction is appropriate.
Send only to those who need it if you can, though usually that is everyone.
WHETHER TO SEND ONE AT ALL
If the broken link was the main action, yes.
If it was a minor secondary link, probably not. Another message annoys more than the error did.
PREVENTING IT
Click every link in the test message. Every time.
This is the most common campaign error and it is entirely preventable by a minute of checking.