USB key - Unable to access device: I/O device error

October 2016


I have removed my USB key without going through the "Safely Remove hardware option" and since then, when I plug-in the device, I'm getting the following error message:
G:\ cannot be accessed.
The request could not be performed because of an I/O device error

How can I recover the data from the device?


To solve this issue, change the transfer mode of your CD-ROM in the properties of the IDE channel. To do this, follow these steps:
  • Click Start, right-click My Computer, and then click Manage.
  • Under Computer Management (Local), click on Device Manager.
  • In the right pane, expand IDE ATA / ATAPI.
  • Right click on the channel to which your CD-ROM drive is connected, and then click Properties. In general, this channel is the Secondary IDE Channel.
  • Under the Advanced tab in the Transfer Mode box of the device that represents your CD-ROM drive, select "PIO Only"

Thanks to Rediam for this tip.

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