This should work with most board versions. I have tested with 2.3.3 and 2.1.7 
It simply allows you to change the "protected forum" text to a link to your boards registration (or anywhere else you want)
Open /cache/lang_cache/ (language) /lang_boards.php
Find...
Change to include your registration link (and if needed the wording)
Simple one...
Taking it a bit further...
Note : You must use <a href='http: and not <a href="http: , otherwise IPB will generate a parse error. If you get an error, double check your code.
Quick screenshot...
It simply allows you to change the "protected forum" text to a link to your boards registration (or anywhere else you want)
Open /cache/lang_cache/ (language) /lang_boards.php
Find...
Code:
'f_protected' => "<i>Protected Forum</i>",Change to include your registration link (and if needed the wording)
Simple one...
Code:
'f_protected' => "<a href='http://www.your boardurl.com/forum/index.php?act=Reg&CODE=00'><i>Protected Forum</i></a>",Taking it a bit further...
Code:
'f_protected' => "<a href='http://www.your_board_url.com/forum/index.php?act=Reg&CODE=00' STYLE='text-decoration:none'><span style='color:#0000FF'><b>Register To View!</b></span></a>",Note : You must use <a href='http: and not <a href="http: , otherwise IPB will generate a parse error. If you get an error, double check your code.
Quick screenshot...