While most data from Chile reach ESO Archive in Garching within one day of the observation via network, the currently available 
bandwidth is insufficient for high data volume instruments, like VST/OmegaCAM and VISTA/VIRCAM data, or burst mode data from other 
instruments. Those data have to be transferred to Garching off-line. This leads to a delay (up to 10 days) between the moment 
when they are visible on the query forms and the moment when they are actually downloadable. During this time, if requested, 
they get assigned the question mark/"DONT_EXIST" flag.
As soon as the data become available in the Archive, the flag is dynamically turned to the green OK flag which means that 
they are accessible and downloadable. This situation is temporary since the bandwidth should be increased by 2012.