farrier

Hi Im a new member in need of a bit of advice.I have just purchased a 2000 Corsa Club 16v its done 500 miles short of 100000 miles and runs OK but the problem is when Ive driven about 60 miles (to work)switch it off I find the engine spins over but wont fire.the first time it happened I eventually locked and unlocked the car and it started,the second time the same again,but the third time I spent an hour doing the same thing going away then going back to it locking unlocking nothing.Im a truck driver and am over the UK Ireland and the continent every time I come back to yard it starts no probs.Ive heard that it could be a problem with the imobilisor is this true and how can I fix it Looking forward to some help from you lads and girls out there. THE FARRIER