I have run into a battery power problem with my 300. I cannot get a battery to connect to it. I can only use the power supply to power the camera. I am not sure exactly where the problem lies, if it's the battery release button not engaging/disengaging problem or something else. The pins that align with the holes in the battery appear to be straight and not bent. I tried three batteries, 2 Sonys and 1 aftermarket, and none of them will connect to the camera. Has anyone else experienced this?

Strange. I wonder if it is worth trying a full factory reset of the camera - just in case it is some software problem? Just an idea.

Thanks, Andy. It appears to be a physical, hardware problem. The battery will not "click" into place like it usually does. I am hoping that it's not an expensive Sony repair. I have taken apart and repaired previous Sony cameras that I have owned myself, but I can't even find a service manual or full exploded view parts schematics for the 300 anywhere. Sony Parts has some, but not what I need.

Whew! Turned out to be a simple fix. One of the four screws on the inside of the battery compartment had become loose, and was sticking out just far enough to prevent the battery from sliding in enough to engage. Tightening the screw was all that was needed. Huge sigh of relief!

Thanks for update. Just checked mine - all 4 screws tight :-)