QUOTE (YorkshireLad6 @ Dec 11 2007, 4:50 pm)

Tickets bought from machines or over the counter are free to exchange or refund if done before the first day of validity, otherwise (as already said) there's a €15 service charge. A refund may also be claimed for tickets only partly used, on provision of adequate evidence, subject to the €15 charge. (§4
Beförderungsbedingungen der Deutschen Bahn AG)
If I'm remembering correctly, if you buy a regional day pass in Munich (like a Bayern Karte) from some vending machines, the ticket will be stamped as valid by the vending machine. Then the ticket will not be refundable. If you buy the same day pass from the vendors at the station, the ticket will not yet be validated until you stamp it yourself. In this case, if you had already bought your ticket from a vendor, but not yet stamped it, they may or may not refund it, but you could at least use it on a different day.
I don't think you needed a gratuitous lecture on "you can't expect to get everything refunded in Germany." That is the kind of snide comment I just hate from people who are ostensibly customer service workers, Beamter or not.