They were divided on others, such as Hotmail's decision in 1996 to promote the e-mail carrier at the bottom of each e-mail sent.

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Also, if you are combining an e-ticketed flight on Carrier A with a traditionally ticketed flight on Carrier B, on the return leg, you must present the voucher to Carrier B to prove that you have a valid booking on Carrier A to fly out of your next stop.

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"We will have a sneak peek of this device at our (Thursday) press conference, " wrote a spokesman for the carrier in an e-mail.

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Currently you can't use an e-ticket to connect with a flight on a different carrier, because the airlines' computers cannot communicate with each other.

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If you hold an e-ticket and your flight is delayed or canceled, you must redeem the e-ticket for a paper ticket to switch to another carrier.

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