Are you using workshop maps ?
- Workshop maps could get updated and you should not upload these maps in "fastdownload" (use workshop system instead for upload maps).
(Not workshop method)
You have exactly same copy of map in srcds and fastdowload ?
Have you Bzip2 compress those fastdownload maps to smaller size?
- Depends a program, but with wrong zip settings you could corrupt your map file and doesn't match any more after decompress.
You should try upload maps as normal *.bsp
Either error say "The map is diffrent from the server", maybe map is too huge.
Client side parameter
-maxdownloadfilesizemb
Read bore here.
[CS:GO] -maxdownloadfilesizemb ???
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