I've been fighting with a WP install on 1&1 (1and1.com) hosting for a couple of days.
I tried everything - server settings, htaccess, php safe mode, double-triple-quadruple checking the db settings in my config.php file, nothing worked.
After trying everything I could find online - and getting nothing but BLANK PAGES in my browser - here's what worked for me...
1. Setup your DB using the 1&1 admin dashboard
(Make a note of your settings, especially your password)
2. Create an FTP account using the 1&1 admin dashboard
(Make a note of your username and password)
3. Download the latest version of WP
(Unzip and get to the root folder with the php files and 3 main folders)
4. Using FTP client, create a new folder for your WP install (my preference)
5. Drag the entire contents of the WP (root) folder to the new folder on your server
MOST IMPORTANT STEP - THIS FIXED EVERYTHING FOR ME
6. Delete the wp-config-sample.php file - and DO NOT manually create a new wp-config.php file!!!
7. Open your browser and navigate to the new WP FOLDER you created.
8. Don't attempt to go to the install.php file or anything else, just go to the folder!
At this point WP should kick into gear and walk you through the rest of the process. Enter your DB info from above, make a note of your admin credentials, WP will handle the rest and drop you into the admin dashboard.
Even now, I'm still convinced I had some setting(s) or entry(-ies) wrong somewhere along the way. Regardless, just letting WP do it's thing naturally worked like a champ.
I'm no expert - don't claim to be - I just hope this helps someone else out there avoid a LOT of frustration...