Herndon-based Internet domain registrar Network Solutions Inc. said it will apologize to tens of thousands of customers whose e-mail addresses the company inadvertently released yesterday. “A few thousand” Network Solutions customers received e-mail messages that contained more than 85,000 e-mail addresses of other Network Solutions customers, said spokesman Patrick Burns of VeriSign Inc., the parent company of Network Solutions. “We made a mistake, and we’ll apologize to our customers,” Burns said. Some customers whose names were included in the mailing said they feared a deluge of unsolicited commercial e-mail as a result of the gaffe. Full Story