Culture ministers attended the launch of Europeana in Brussels
The European Union's huge digital library Europeana, which crashed last month just hours after its launch, is back online.
The website's server capacity has been quadrupled to cope with demand, European Commission spokesman Martin Selmayr told reporters.
But the homepage - at www.europeana.eu - warns that "the user experience may not be optimal in this test phase".
The site gives multilingual access to cultural collections across the EU.
The site was swamped by users on its launch on 20 November, with a volume of 10 million hits an hour, triggering a crash.
Europeana brings together more than two million books, maps, recordings, photographs, archive documents, paintings and films.
Many of Europe's top museums, such as the British Museum and the Louvre in Paris, have contributed to the project.
It is hoped 10 million works will be available on the website when it is fully operational in 2010.