I had the same problem once.
What I ended up doing was ejecting and inserting the tape and it was fine... Don't know if this will helop you guys but It can be worth trying.
I also had it happen to me when the tape has been write protected but this was pretty obvious...

DrGonzo

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P4 2.2GHz, 512MB RAM, 60GB OS, 250GB WD Media Center FW/USB2, Sony DCR-PC105e, Sony wide angle conversion lens
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