Each week, I talk to clients about sending out weekly/monthly newsletters via Passle. People are always very keen on the idea, as they understand that regular newsletters are a perfect way to drive visibility on their content, boost their webtraffic and keep their brand in the front of their customers' minds.
However, 9 times out of 10, people tell me that their mailing lists are out of date and need 'cleaning up'. To most people, this is a chore that falls straight to the bottom of their to-do list, and lo and behold, it never gets done. Ultimately, this delays the one-minute process that is creating a newsletter with Passle.
My advice is to start afresh. Ask your colleagues to contribute 20 valuable email addresses each. Then each time you send your newsletter, ask those same colleauges to suggest a few more. You'll quickly find yourself with a highly relevant mailing list, full of the 'right' people. I'd also bet that your key metrics, like click-through and open rates, will improve too.