If you can move the shifter in and out of each gear with and without the engine running then I would suspect the cables that transmit movement to the shifter fork on the transmission.
You might be able to check the cables (2) at the transmission shift fork to see if any of them have disconnected causing the shifter to sieze in place.
This problem is usually on the transmission side but could also be on shifter side of the shifter cables.
If you can shift gears with the engine off then I would suspect the clutch is not fully releasing with the clutch pedal depressed.
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Monday, December 9th, 2013 AT 9:51 PM