I have an SX120 with WinXP. sx120is-100b-0.9.9-912-full -- SD card reader adapter to USB.
My camera has worked fine with CHDK for months, no new software.
I'm having a similar problem, my almost full 4G SD card shows as write protected. The write protect tab works on-off OK in the camera, (splash screen, alt mode, etc) but it acts like the tab is protected when I try to delete or save/modify files. (Yes, I have a few RAW pics.)
(FYI, one web search answer says it's a registry error, but other SD cards seem fine. It seems like this one card only has somehow been protected (similar to a format?). )
Two questions. 1) Is there a fix? 2) Is there a work-around such a way to mass-delete (say, a folder,) from a camera menu so I can reuse it?