There is a real difference between "May I send you an email?" and "Can I send you an email." And I'm not just talking about which question to ask your prospective subscriber. In case you're wondering now that I've mentioned it, WordTask defines "may" as expressing permission or possibility, while "can" expresses ability.

In email marketing, the first question..."May I send you an email?" is the essential question you're asking your prospective subscriber when getting permission to send her an email. This is where you need to be really clear about what you're asking permission to send, and she needs to be really clear about what she's giving you permission to send.

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The "Can I send you an email" is an entirely different story. Your ability to actually deliver the email is, however, is still a bit of permission. Not so much the asking permission...the "May I?" because there's really no one to ask permission of...but the finding out through testing whether you can actually get the email to move all the way from your "out basket" to your intended recipient's "in basket."

This is the more technical side of email marketing, and it can be much trickier. The "can" for email marketing consists of whether your prospective subscriber has the right kind of software to receive your email in the format you've designed it...and...(the part about finding out if you got permission without saying "Mother may I?" is whether you can (have the ability to) get your content and layout to pass through the permission police of the numerous spam filters currently used by Internet Service Providers (ISP's) as well as any additional filters added by your prospective subscriber.