Adobe Media Encoder Unknown Error

I'm trying to export an Adobe Premier Pro file on Adobe Media Encoder. Each time I try, it gets about halfway through, then this error message comes up:

- Source File: /Users/A25/Library/Caches/TemporaryItems/Incubus Trailer Rough Cut.prproj

- Output File: /Users/A25/Desktop/Odyne Theatrical Trailer.mp4

- Preset Used: HDTV 1080p 25 High Quality

- Video: PAL, 1920x1080, 25 [fps], Progressive

- Audio: AAC, 160 [kbps], 48 kHz, Stereo

- Bitrate: VBR, 1 Pass, Target 32.00, Max 40.00 [Mbps]

- Encoding Time: 00:07:07

Mon Apr 15 12:48:21 2013 : Encoding Failed

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Error compiling movie.

Unknown error.

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I've tried different video presets (1440x1080, 1920x1080 etc), but this message has appeard every time. Any ideas how to export it?

Thanks