internal server error

I get a fail 43% of the way into db copy log goes along until:
——-
[02-04-2016 14:11:15] Copy database table: wp_options
[02-04-2016 14:11:18] Copy database table: wp_options DB rows: 500
[02-04-2016 14:11:18] Copy database table: wp_options
[02-04-2016 14:11:20] Copy database table: wp_options DB rows: 700
[02-04-2016 14:11:20] Copy database table: wp_options
[02-04-2016 14:11:23] Copy database table: wp_options DB rows: 900
[02-04-2016 14:11:23] Copy database table: wp_options DB rows: 900

——
then repeats the last line shown here ( a few 100 or so times) until it fails.
thanks,
John

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