Versioned::get_version: Couldn't get SiteTree.1

For some reason the code is trying to get a SiteTree versioned object that doesn't exist. From looking at the backtrace is originates from a template file so it could be a caching issue so try visiting admin/?flush=all rather than admin/ to flush that out.

If you have just installed SS, then I suggest dropping or emptying the database and running dev/build again and see if you have any issues. Make sure dev/build is successful by scrolling all the way to the bottom of the page.

Nevermind...reinstalled and tried again. Works fine until i import my own database. After that the login page gives me the same error as before except that flush all didn´t work this time
So I emptied my database (as you suggested) and did a dev build. Again all went back to normal. Login worked and all. But re-importing my database doesn´t work anymore due to the following cause:

ERROR

SQL-command:

--
-- database: `rs_reisen`
--
-- --------------------------------------------------------
--
-- table structure for table `ArticlePage`
--
CREATE TABLE `ArticlePage` (
`ID` int( 11 ) NOT NULL AUTO_INCREMENT ,
`Date` date DEFAULT NULL ,
`Author` mediumtext,
PRIMARY KEY ( `ID` )
) ENGINE = MYISAM DEFAULT CHARSET = utf8 AUTO_INCREMENT =29;

MySQL reports: Documentation
#1050 - Table 'ArticlePage' already exists

so is there anything wrong with my database? although it says "articlepage" already exists the database shows zero tables in myphp