Bit more diagnostics, as I am still not sure whether issue is with the router, SharePort or the Seagate drive.
Tried a robocopy copy of a 4.3 Gb file in restartable mode. This fails every 3 minutes or so (but restarts) finally completing at a rate of 67 MegaBytes/min...
...
64.7% New File 4.3 g THE_WEST_WING - Disk 2.ISO
2013/05/07 20:43:39 ERROR 64 (0x00000040) Copying File Z:\Video\TV Series\West Wing Series 1\THE_WEST_WING - Disk 2.ISO
The specified network name is no longer available.
Waiting 30 seconds... Retrying...
67.2% New File 4.3 g THE_WEST_WING - Disk 2.ISO
2013/05/07 20:46:09 ERROR 64 (0x00000040) Copying File Z:\Video\TV Series\West Wing Series 1\THE_WEST_WING - Disk 2.ISO
The specified network name is no longer available.
Waiting 30 seconds... Retrying...
85.1% New File 4.3 g THE_WEST_WING - Disk 2.ISO
...
If I check the router logs at the failure times, say from the error above about 20:46:09 I can see an error reported and the drive being re-mounted...
[Time]Tue May 7 20:46:04 2013
[Message:377]ntfs_attr_pread_i: ntfs_pread failed: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:378]Failed to read vcn 0x2: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:379]ntfs_attr_pread_i: ntfs_pread failed: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:380]ntfs_attr_pread error reading '/Video/TV Series/West Wing Series 1/THE_WEST_WING - Disk 2.ISO' at offset 3146219520: 4096 <> -1: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:381]ntfs_attr_pread_i: ntfs_pread failed: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:382]Failed to read vcn 0x2: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:383]ntfs_attr_pread_i: ntfs_pread failed: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:384]Failed to read vcn 0x0: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:385]ntfs_attr_pread_i: ntfs_pread failed: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:386]Failed to read index block: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:387]ntfs_attr_pread_i: ntfs_pread failed: Input/output error
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[Time]Tue May 7 20:46:07 2013
[Message:388]Failed to read vcn 0x2: Input/output error
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[Time]Tue May 7 20:46:08 2013
[Message:389]Unmounting /var/tmp/sda1 (Seagate Expansion Drive)
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[Time]Tue May 7 20:46:09 2013
[Message:390]( (1020)action 1,major 8,minor 0)
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[Time]Tue May 7 20:46:09 2013
[Message:391]( (1021)action 1,major 8,minor 1)
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[Time]Tue May 7 20:46:09 2013
[Message:392]umount (/tmp/sda : /tmp/storage/Seagate_Expansion_R7TJ0) success
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[Time]Tue May 7 20:46:19 2013
[Message:393]Version 2010.10.2 integrated FUSE 27
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[Time]Tue May 7 20:46:19 2013
[Message:394]Mounted /var/tmp/sda1 (Read-Write, label \"Seagate Expansion Drive\", NTFS 3.1)
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[Time]Tue May 7 20:46:19 2013
[Message:395]Cmdline options:
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[Time]Tue May 7 20:46:19 2013
[Message:396]Mount options: allow_other,nonempty,relatime,fsname=/var/tmp/sda1,blkdev,blksize=4096
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[Time]Tue May 7 20:46:19 2013
[Message:397]Ownership and permissions disabled, configuration type 1
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[Time]Tue May 7 20:48:19 2013
[Message:398]Web login success from 192.168.0.100
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