Cannot login

[Ted]

Just shutdown and rebooted my box and when I try to login it tells me
Your session only lasted less than 10 seconds...Try logging in with one 
of the failsafe options to see if you can fix this problem...Then
View details ~/.xsessions-errors file..
I have looked at this file and nothing seems wrong....I did a mv and 
rebooted
and the same error came up and the same xsessions-errors appeared..
Anyone an idea of what I should be looking at....
The box had been running for a couple of weeks ok  so I don't know why
it should come up with the 10 second bit....

-- 
Regards
  Ted Wager
   Linux user