Help! Blanc page on Joomla Administration page - Joomla! Forum - community, help and support

hello,
i hope joomla experts can me - did nothing joomla files, administration page quite blanc: http://www.modemand.dk/administrator/,
please, how fix problem?

it unlikely "did nothing" or more worryingly site may have been cracked or host has done server has caused issue.

comparing source code of login page default login page using same template login on page has substantially more code dealing ie4 & netscape4 , missing other information.

therefore question should using default login extension or 1 have installed/modified?