Problems changing domaine

[trp-dk]

Hi all
Hope this is the right place to post, and REALLY hope for some help.
I´m dane (excuse my English) and enherrigded the admin job a few days ag because of sudden illnes. I´m a total newbie to this. End of introducing. 
Story: The Forum for many years belonged to an educational publishing Company that recently wanted to close it. As favour to the users (old machinists) the agreed to transfer it to a private domaine on hxxp:one.com [nonactive].
It worked great for a few weeks, until One com suddenly upgrated all php5,5 to php7. Caused total colaps
The domaine is now running php.5,6 and i know that a One com supporter helped moving som files to make the forum start again.
It did, but only the opening/index page. Trying to enter one of boards made it jump back to the old server.
Thats where I became admin
I changed some path´s in the php settings, and managed yesterday to make it stay on the domain.
Only it did not recognise the 3 special Danish letters, and coulld not show attachments (Pictures) further i got this message when opening the forum:
Deprecated: preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in /customers/1/0/2/frylund.dk/httpd.www/forumfagteori/Sources/Load.php(225) : runtime-created function on line 3
Today when opening, I only get the message, but can´t enter the forum. ??
I can find the sourches/load php (line 3 only says load php) but the message is "chinese" for me.
I really hope for some help, and PLEASE write as detailed as possible.
Thanks
Tommy

[Illori]

you need to upgrade to SMF 2.0.11. http://wiki.simplemachines.org/smf/Patching

[trp-dk]

Hi
Thankyou for answering so quick.

Unfortunally I´m afraid it´s over my skills. 

The domaine is now running php 5,6. Should SMF not be able to Work on that?

[Illori]

you NEED to upgrade, no questions asked.

[trp-dk]

Clean speach Thankyou!
I´ll start to study.

[Kindred]

more specifically  no, SMF 1.1.x will not work cleanly on php 5.6  which is why you need to upgrade.