With no disk loaded: Press the Menu button on your remote control
Press the 5 button on your remote control
Press the 7 button on your remote control
Press the 5 button on your remote control
Press the 3 button on your remote control
Press the 8 button on your remote control The currently selected region will be indicated on the onscreen display Press the 1 button on your remote control for region 1, the 2 button for region 2, and so on, or the 9 button for multi-region playback Press the Menu button on your remote control
Press the Menu button on your remote control tried this a couple of times but got no joy, but then on my third attempt I pressed the open/close button on the remote by accident instead of pressing Menu twice & hey presto my sr150m is now multiregion!! Give it a go