my iphone 4 doesnt show up on 'my computer' and picasa doesnt recognise it either, although the itunes sync does seem to be working fine and it does show up in devices and printers. the main thing i need is to be able to access my photos. thanks
I had the same problem once, found this solution on another forum and it worked for me.
Follow these steps
1) Go to Device Manager
2) Right click on the iPhone slot and click "update driver"
3) On the window, click next, then click the "advanced" option on the next screen
4) Check the second box and type in "C:\Windows\INF" (without quotes) in the textbox
5) Let windows install the driver
6) Connect to iTunes, if you get an error, turn off the iPhone while plugged in and turn it on again, it should work