I have had similiar problems since Oct. with calibre not being able to send books to the SD card. IOerror 22.
I thought at first that it was because I had too many books on card and eventually reformatted card to fat 32 with no difference.
Tried a lot of things with no luck
Recently had problems with database and reimported all ebooks into new database using version 7.52
Calibre would no longer communicte with my device (communication failure)
reformatted Sony PRS 600 main memory and SD card
Sent 300 books to device (SD CArd)
Worked fine
Sent 8 more books
Reader went into fibrillation mode with the little circle whirrring until the battery died.
Recharged and went through this repeatedly for about 36 hours
I was thinking cable or SD Card at this point.
Plugged reader into different computer with Calibre 7.17
Seemed to work ok, read books on device/sd card but still/was able to send books to SD card but still when I disconnected the reader just displayed circle with arrows turning until the battery ran out.
In desperation I reconnected to original computer without calibre running and ran Sony reader software
Sent 8 books to SD card. Charged battery, disconnected reader, and it worked.
Pretty sure it is not a calibre problem as there are a lot of users with Sony PRS-600
Have used 3 SD cards with same message coming up after I have had them connected using Calibre (scan card message from Windows 7) and same inability to write to them using calibre after the inital write.
Cable seems to work fine with Windows XP and Calibre 7.17. Or on Windows 7 with Sony reader software.
No random disconnects that I can determine.
calibre is excellent software and I have even taught my 86 year old mother to use it after a fashion. (must donate on her behalf
, but for some reason I am having a lot of Sony PRS-600 issues these days which all worked (still seem to) with earlier versions.
Not the end of the world as I can still put books on with Sony software but any insight appreciated
Helen