Piggybacking as well, had the exact same problem. Turns out our power company had a scheduled outage that I wasn't aware of, and my computer was shutdown.
I've tried copying some of my files over to a new galaxy (with the same seed) to try and isolate the problem. So far, the "factions" and "players" folders seem to work (i.e. don't cause hang-ups); the new galaxy loads, though I don't see any of my old stuff, whether it's resources, upgrades, or even the list of factions (though I imagine those might reappear once I explore the relevant sectors again).
However, the "sectors" folder, along with the "jumps.dat" and "jumpsmeta.dat" seem to be causing hang-ups.
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I'm copying the contents of two logs: the first is the last portion of the log prior to the shutdown. The second is the full log from my first attempt at launching the game after the shutdown. Every subsequent log appears to be more or less identical. I bolded the error in the second log.
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2017-06-18 21-51-00| saving sector (31:247)
2017-06-18 21-51-00| sector (31:247) saved to "C:\Users\Fred\AppData\Roaming\Avorion\galaxies\Second Galaxy\sectors\31_247"
2017-06-18 22-00-37| starting event alienattack
2017-06-18 22-01-00| Triggered saving of all server data.
2017-06-18 22-01-00| scheduled save for sector (31:247), 0x28fc3f60, entities: 1210
2017-06-18 22-01-00|
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2017-06-18 22-12-48| Enabled Traces:
2017-06-18 22-12-48| Avorion server Beta 0.11 r7857 running on Windows 8.1+ starting up in "C:\Users\Fred\AppData\Roaming\Avorion\galaxies\Second Galaxy"
2017-06-18 22-12-48| CPU: GenuineIntel 12 Cores
2017-06-18 22-12-48| name: Varthorne's Server
2017-06-18 22-12-48| seed: LastSeedBlarghGalaxy
2017-06-18 22-12-48| port: 27000
2017-06-18 22-12-48| max online players: 10
2017-06-18 22-12-48| save interval: 600
2017-06-18 22-12-48| broadcast interval: 5
2017-06-18 22-12-48| max loaded sector time: 300
2017-06-18 22-12-48| weak update: yes
2017-06-18 22-12-48| worker threads: 11
2017-06-18 22-12-48| generator threads: 2
2017-06-18 22-12-48| difficulty: Normal
2017-06-18 22-12-48| infiniteResources: no
2017-06-18 22-12-48| collision: 0.5
2017-06-18 22-12-48| access list: Blacklist
2017-06-18 22-12-48| public: no
2017-06-18 22-12-48| authentication: no
2017-06-18 22-12-48| listed: no
2017-06-18 22-12-48| steam networking: yes
2017-06-18 22-12-48| server will exit once all admins logged out.
2017-06-18 22-12-48| administrators: 'admin'
2017-06-18 22-12-48| Initializing sector database...
2017-06-18 22-12-48| Initializing faction database...
2017-06-18 22-12-49| Starting up 11 worker threads...
2017-06-18 22-12-49| Loading jumping entities...
2017-06-18 22-12-49| Loaded 48 jumping entities.
2017-06-18 22-12-49| Loading groups...
2017-06-18 22-12-49| Galaxy initialized.
2017-06-18 22-12-49| An exception occurred: DataStream access error: Accessed data exceeds buffer size: 0, offset: 0, access size: 4
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