Random Write errors in Win2003 server - From WMencoder

This is a very annoyng problem, hope anyone helps:

I encode different audio & video sources directly to 15 minute WM9
files, whose I record on Network Share. Encoders run on different XP
Pro machines, up to 5 encoders per box. All machines are in the same
100mb LAN, same domain and logged as Adminstrator. I encode using
standard WMENC Gui and also VB Scripts and VB Net apps (No gui); about
40 audio & video sources at the same time. Altough this, server load
is not high, since streams are very low bandwidth (16kb audio; 88kb
video)

When I had a Win 2000 Std Server as a file server (P4, 1ghz) ,
everything worked smoothly. I managed to encode more than 2 Terabytes
of files, 24 hrs a day, for two years.

But then I switched to a brand new, more powerful (P4 3 ghz) Win 2003
Std server, write errors began to raise on the encoders, on a random
basis. Error number on Windows Media Encoder log is 0xC00D0018
(NS_E_FILE_WRITE) and it happens very seldom, about 1 for each 100 or
200 15 min WMV or WMA files. It can happen anytime: when there are
just 2 or 3 sources recording, or the full 40. It can happen in any of
the 10 machines i use for encoding, so i beleive the encoders are not
the problem.

There are not related errors or messages on the win 2003 server, nor
in the encoder xp pro machines. I beleive also it is not a
hardware/cabling problem, since there are not any other problems in
several proceses I run on the system: Database, IIS services, etc.

When the error happens, the file corrupts at that point, and even if
the file continues to be recorded, no more audio or video beyond it.
Files cannot be fixed by any means.

Of course, error does not appear when recording to local drive, but it
is useless to me.

I read in Q275920 that this error happens when IWMWriter::WriteSample
method executes when "The file sink close method executes before all
the samples queued in the writer are committed to disk. This causes an
invalid handle error in the file sink, which is returned as
NS_E_FILE_WRITE. The writer checks the last status of the file sink
before queuing more samples in WriteSample and detects the
NS_E_FILE_WRITE error state in the writer, which it then returns to
the caller."

But this was a Windows Media 7.0 SDK issue, wich was corrected in
later versions, i beleive.

So.. anyone has an idea of what would be happening?

I know there would be thousands of reasons, and perhaps there are not
related to windows media itself, but.. where can I start?

Thanks in advance for your help and greets from México City.

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