Open the file it mentions and paste the line 194 here

Possibly a too old version of php. If you are trying to install Elgg 1.10 and the php version on the server is 5.3 or older, the installation will not work because Elgg 1.10 requires php 5.4 at minimum.

Not my install as its on an ELGG hosting site - must be their fault.

thx iionly - at least it wasn't my fault this time :D

php version upgraded and I can now get on the site though this error message appears across the top and screws up the display.

Warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/jedsitei/public_html/engine/lib/elgglib.php on line 918

Seem to have fixed it by flushing the caches (again)

try adding

ini_set('date.timezone', 'America/Los_Angeles');

after the opening <?php tag in your theme.

Here's a list of supported timezones:     http://php.net/manual/en/timezones.php