Upgrading Drupal

I upgraded from 5.1 to 5.6 directly, without any issues, but when I want to post to a forum I get the following:

Hi all,
I am actually looking for a module which is used to set all title of the form like "Forum","Edit Content ","Download" etc manually.Is there any module available for that....?

Hey all. i am new to drupal....I used joomla for 1,5 years... but 2 weeks ago installed drupal 6.0 rc2...and was amazed by flexibility and ability to make many customizations.

The question is if I install the RC2 to a production site...and when RC3 will be shipped or later 6.0 Final - won't it be a problem of online upgrade of the site from RC2 to Stable version ?

And when approximately the stable release will be shipped?

Thanks a lot for your responses.

Roman

After upgrading a test site from 4.7.3 to 5.5, most things seem fine, but when I click on a link to an individual forum post I get this fatal error.

Fatal error: Call to undefined function: module_exist() in /home/public_html/test1/themes/foliage/node-forum.tpl.php on line 15

The forum post titles show up, the forum categories are as expected, but the forum posts themselves crash to an error when clicked.

Hello,
I've upgraded from version 5.3 to 5.5, with Localizer, and i've got this message on every page, which basically bring the site to a grinding halt...

Fatal error: Call to undefined function calendar_info() in /srv/www/dd-rd.net/cms/drupal/modules/calendar/calendar_ical.module on line 20

A) Any known issues about ical? (Which i'm not even using). If the module hasnt changed, could this be due to database corruption? (I've reinstalled a previous version, which worked for a few days, than stopped again...)

After upgrading to Drupal 5.6 my image galleries come up empty at the lowest level. I can see thumbnails at the gallery root, can drill down into individual galleries and see sub-gallery thumbnails (and even view images of these Gallery Lists with Lightbox2).

But when I drill down to the actual gallery where all of the images should display, the page is empty.

I have not encountered this problem in upgrading from previous versions. I also upgraded the image module to Image 5.x-2.x-dev (2008-Jan-10).

Help in sorting this out is appreciated ...

Bob