[help]I can't find autoexec.cfg

My OS:windows 7 Ultimate x64
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When I enter 'teeworlds_srv-f serverconfig.cfg' after the show:
D:\game\teeworlds>teeworlds_srv.exe -f serverconfig.cfg
[4d1ed673][engine]: running on windows-win32-ia32
[4d1ed673][engine]: arch is little endian
[4d1ed673][storage]: added path '$USERDIR' ('C:\Users\long\AppData\Roaming/Teewo
rlds')
[4d1ed673][storage]: added path '$DATADIR' ('data')
[4d1ed673][storage]: added path '$CURRENTDIR' ('D:\game\teeworlds')
[4d1ed673][console]: failed to open 'autoexec.cfg'
[4d1ed673][console]: failed to open 'serverconfig.cfg'
[4d1ed673][datafile]: loading. filename='maps/dm1.map'
[4d1ed673][datafile]: allocsize=2308
[4d1ed673][datafile]: readsize=2148
[4d1ed673][datafile]: swaplen=2088
[4d1ed673][datafile]: item_size=1776
[4d1ed673][datafile]: loading done. datafile='maps/dm1.map'
[4d1ed673][server]: maps/dm1.map crc is f35c9309
[4d1ed673][server]: server name is 'unnamed server'
[4d1ed673][datafile]: loading data index=16 size=325 uncompressed=12000
[4d1ed673][server]: version 0.5 b67d1f1a1eea234e
[4d1ed673][engine/mastersrv]: refreshing master server addresses
[4d1ed673][register]: refreshing ip addresses
[4d1ed675][engine/mastersrv]: saving addresses
[4d1ed675][register]: fetching server counts
[4d1ed676][register]: choosen 'master3.teeworlds.com' as master, sending heartbe
ats
[4d1ed6ad][register]: ERROR: the master server reports that clients can not conn
ect to this server.
[4d1ed6ad][register]: ERROR: configure your firewall/nat to let through udp on p
ort 8303.
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Client and the server is running no problem, but the server can not configure, because they can't find the 'autoexec.cfg' file.