I've had this error before and from the size of the posting list when you search for it my guess is a lot of others have too. I had a perfectly working site and then decided to edit the site information, in particularly the slogan.
All I can tell that I did differently was reach the limit a few times for text length before I settled on the final text. Also the final text had an ampersand in it to use fewer characters.
Bang! Site was down. No long ins. I got a message like this:
Fatal error: Cannot redeclare date_api_views_data() (previously declared in /home/uminalt/public_html/drupal/sites/all/modules/date/includes/date_api.views.inc:123) in /home/uminalt/public_html/drupal/sites/all/modules/date/date_api.views.inc on line 60
I solved the problem and got the site back up. Here's how.
I logged into the site using SSH and went to sites/all/modules then I used the mv command to move the offending module, in this case date, to my home folder (mv date ~/) then I got a similar error message from calander so I moved that too. Suddenly I could log in. I did, edited the slogan, removed the ampersand, and then put the modules back where they were (cd ~ followed by mv date sites/all/modules etc).
Everything started working again.
You might expect the moral of the story is don't use & in your slogan but I think I've done that before. Anyway, the technique might work for you. You move the offending module until the redefinition warnings stop, log in, retrace your steps, put the modules back, and you're good to go.
Len Umina
WT6G
