[jszentes]

It still does not work. There are 2 failure modes

1. Manually delete driveinfo.calibre from device. Calibre connects to device but then suffers from a memory leak which eventually consumes all system memory before crashing. The Calibre Jobs window shows it is "Reading ebook metadata" from the device.
Incidentally a deviceinfo.calibre file is created on the device.

2. Connect to device with deviceinfo.calibre file. This fails with the error I previosuly listed about not being able to write the deviceinfo.calibre file. Which is true because the timestamp of the file in the device is not updated.

All this was done while the device screen was not locked.

I should also note that I have no problems reading/writing files on the device using the pcs' file manager.