Double opt in error

What does this error mean?

Warning: set_time_limit() has been disabled for security reasons in/home/fhlinux221/e/emaress.co.uk/user/htdocs/ktc/userupdate.php on line 319

Currently, I have it on a temporary server which doesn't match the domain, so is this the reason for the error?

Thanks

in the universal email code block, we use the following to set the time limit for the script to infinity:
set_time_limit(0);

this is done so that the script will time out on large mailings to many recipients.

your host has disabled the set_time_limit() function

to work around the error, change:
set_time_limit(0);

to:
@set_time_limit(0);

the @ symbol at the beginning of the line will suppress errors.