I seem to have a problem that relates to Firebird, IBReplicator or Windows/Domain permissions. The trick is to understand which.

I understand that this forum relates to Firebird, but I figure that some firebird guru's out there might be able to decipher the errors that I'm seeing the firebird log. I am also hoping that others might have experienced past issues where Windows/Domain permissions have affected Firebird and which might explain what I'm seeing.

Below is the background to the issue and details on the errors that I am seeing...

I have 2 servers. Each running Windows 7 Enterprise (Service Pack 1) and each running Firebird 2.1.4.18393 Win32.
IBReplicator (version 4.1.0) is running on one server and has replication scheduled to take place every 60 seconds.
Both servers were working well in our office. They have since been sent to site, attached the the site's network, and replication is now not working.
As a diagnostic step, both servers have had their firewalls and antivirus disabled.
The server IPs have changed now that they are on site (Hospital with large internal network). However, the replication references each other via their computer names (eg. BOX3 and BOX4), so I don't believe I need to change anything within IBReplicator.
Note: A ping of BOX3 and BOX4 works fine.
Note: I can remotely access these servers using VNC, so that also verifies that network connectivity works.

With regard to how Firebird and IBReplicator was installed, they were installed within a Windows user account that is a member of the Administrator's group, and was installed in an environment that was not running a domain. However, now that they are on site, the server runs as a member of the hospital domain.

Extract from C:\\ProgramData\IBPReplicator\Replicate.log:

02/23/13 10:48:39: ******************* Start Replication ********************
Replicate BOX3->BOX4, BOX3 -> BOX4
02/23/13 10:48:49: Connected to DB: \\BOX3\C:\Program Files\Solution\Database\Solution.fdb
02/23/13 10:48:49: Connected to DB: \\BOX4\C:\Program Files\Solution\Database\Solution.fdb
02/23/13 10:54:07: Error (id "TFBDB::ExecuteSelect - execute") happen during execution of schema BOX3->BOX4 (BOX3 -> BOX4)
Update MESSAGEHISTORY 301946
Unable to complete network request to host "BOX3".
Error reading data from the connection.
The specified network name is no longer available.
Unsuccessful execution caused by a system error that precludes
successful execution of subsequent statements
Replicate BOX4->BOX3, BOX4 -> BOX3
02/23/13 10:54:07: Disconnected from DB: \\BOX4\C:\Program Files\Solution\Database\Solution.fdb
02/23/13 10:54:07: Connected to DB: \\BOX4\C:\Program Files\Solution\Database\Solution.fdb

Extract from C:\\Program Files\Firebird\Firebird_2_1\Firebird.log:

C:\Program Files\Firebird\Firebird_2_1>tail firebird.log
tail v1.30 (c) Greg Robson-Garth, 1998-2001
25:07 2013
WNET/wnet_error: WriteFile errno = 64

BOX4 (Client) Sat Feb 23 10:30:55 2013
WNET/wnet_error: WriteFile errno = 64

BOX4 (Client) Sat Feb 23 10:30:55 2013
WNET/wnet_error: WriteFile errno = 64

BOX4 (Client) Sat Feb 23 10:30:55 2013
WNET/wnet_error: WriteFile errno = 64

BOX4 (Client) Sat Feb 23 10:32:07 2013
WNET/wnet_error: CreateFile errno = 64

C:\Program Files\Firebird\Firebird_2_1>

My current view on the most likely reason is that there is perhaps some Domain profile being applied to the servers that is preventing IBReplicator from connecting via Firebird (presumably because Firebird needs to create some temporary files somewhere, and because it can't, these issues are occurring).
However, I know very little about Domain induced restrictions, so before making a silly assumption and asking the Hospital IT staff to act on it, I'd like to understand these WriteFile and CreateFile errors that I'm seeing in the firebird.log. i.e.

Do these errors occur when Firebird is not permitted to create/write to some temporary file somewhere? If so where?

Or, if these files relate to network communications, do these errors simply get created when a network communications issue occurs?

Or, if IBReplicator was able to connect, transfer the replication instruction, but not be able to execute the instruction, would it terminate proceedings ungracefully and then cause Firebird to report these created/written errors?