Bei mir trat auch das Problem auf, daß nach dem Download nicht auf die Speicherkarte geschrieben wurde - mit entsprechender Fehlermeldung (unter Vista). Nach der Deinstalltion vom ATI Catalyst Control Center funktionierte es dann. Aber Achtung nur das Control Center deinstallieren und nicht alles (Treiber) von ATI 
Hier auch noch ein Link dazu (englisch):
http://discussions.nokia.co.uk…=pcsuite&message.id=18136
Falls der Link irgendwann nicht mehr funktionieren sollte, hier das wichtigste:
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Instructions for a Nokia mobile phone user using Nokia Map Loader to download maps, which produces the following error message "Connection to the storage medium has been interrupted. Attach your storage medium and retry."
The interruption connection problem is caused by another application on your PC - ATI Catalyst Control Center, which requires uninstalling for the Map Loader to work.
It took me 3 days of searching the Internet forums to find this solution –thanks to a user called ‘Galazar’ I thought it would be a good idea to post a complete instruction list to help everyone out.
Instructions:
1 Right-click the ATI symbol on the System Tray next to the digital clock. Choose ‘Exit’ to exit the ATI Catalyst Control Center programme from your PC memory.
2 Control Panel –Click on Programs & Features (Classic View) or just Programs (std view)
3 Click on ATI Catalyst Install Manager then ‘Change’ button in between ‘Views’ and ‘Repair’.
4 Click ‘Next’ button to continue.
5 Click on ‘Uninstall Manager’ radio button and then ‘Next’ button.
6 On the Welcome screen choose ‘Custom’ radio button then ‘Next’ button.
7 On next screen ‘Component Selection’, click on tick-box for ‘ATI Catalyst Control Center’ then click on ‘Next’ button.
8 Once the uninstall has completed and the application exited I recommend your restarting Windows to completely remove it from the System Registry (automatically).
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