The manual:
http://products.bose.com/pdf/customer_service/owners/AM312515_01_321_SeriesIIIandGS_OG_ENGvo.pdf
The history evn on Fixya alone is not good for this error...
http://www.fixya.com/support/t251763-bose_lifestyle_38_unsupported_format
Solutions 2 thriough 5
Reset:
1) Turn around the lifestlye system so you can see all the cables. First unplug the cable which connects the lifestyle system to the huge acoustimass module (bass speaker). It is a roundish 8 pin cable - on mine it was in the second column of slots from the left. Labelled main. under the power input plug and above a slot labelled Boselink. If you have one in the Boselink instead, unplug that as that is what he was originally trying to get me to unplug but I didn't have anything there.
2) Second, unplug the DC power cord just above it
3) wait at least a minute
4) plug the power back in
5) plug back in the first cable to the acoustimass
The order you do this is apparently important.
Clean the lens:
All you have to do is carefully take the top off and clean the "Iris" which is the reader with a little alcohol and cotton swab. Bose will charge $165 plus shipping to do this. Go to website metacafe.com and search how to clean DVD players and it will show a video, easy to understand.
Call for help:
I'd call Bose and make the case
1-800-999-2673
Sales support:
Mon. - Sun., 7 AM - 2 AM ET
Technical support:
Mon. - Fri., 8:30 AM - 9 PM ET
Sat., 9 AM - 6 PM