help with dvd region reset please

[RVafiadis]

I have a Toshiba a215 satellite running windows vista. I am trying to reset my dvd region back to region1. It tells me that I have one more change I can make. I set the new region to 1, click ok...I get the message that this is the last time I can change it and I click OK to proceed. Then another message pops up saying that the region cannot be changed until a media with the destination region (region 1) is in the drive. I insert a region 1 dvd and try again...I get the same messages over and over again! Can anyone tell me what is wrong? Thanks.