Error 503. Service temporarily unavailable.
The server temporarily cannot process the request due to some technical reasons (maintenance, overload etc.). In the Retry-After field of the header the server may specify the time in which it recommends the client to repeat request. Also it is possible that the server has limitation on the number of connections from one IP-address.
Try to download later
Possibly the server works unreliably. Try to download the file later.
Reduce the number of download sections for this file or server
To limit the number of sections in the Download Properties window press the Advanced button and enter 1 in the Limit maximum download sections field. To limit the number of download sections for all downloads from a particular site add this site to the Site Manager and set there the desired limitations. Start download.
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