Printer GPOs fail on some computers but work on others - error code 0x80070034

Question

Hello, I have a couple of GPOs that roll our printers. They have been running smoothly for quite some time, then suddenly started giving our errors on our newer machines. Meaning, the GPOs will work fine on some clients but will not work on others. Also
all other GPOs work fine on all clients. The clients are similar Lenovo Windows 7 64-bit machines.
This is the error: Event ID: 4098, Group Policy Printers. The computer '123.123.123.123' preference item in the 'Deploy printers - {3F6DE6D0-86DC-4D1F-AB99-81BC07F23F3C}' Group Policy object did not apply because it failed with error code '0x80070034 You
were not connected because a duplicate name exists on the network. If joining a domain, go to System in Control Panel to change the computer name and try again. If joining a workgroup, choose another workgroup name.' This error was suppressed.
I turned every stone I could think of on the problematic machines but cannot find out a reason. I disabled anti-virus/firewall, I logged in as domain admin and I tried both user & computer GPOs. No luck. Notice that I can successfully connect manually
to the Printer shares (the ones used to distribute the drivers).
Domain is Win2008 R2. The printers "live" on a Win2012 machine and the drivers come from there. I am using Group Policy Preferences. Ideas are welcome.
Thanks
Christos

Answer 1

Hello and thanks for the suggestion. Yes the drivers are okay, all clients (working and not) run the same Win 7 x64. Let me summarize the situation:
- The GPO runs because the printer IP ports are created
- The Printer Shares (that distribute the drivers) are accessible because the printer is installed without any problems/warnings if I manually double click on them (the shares)
- Security prompts for driver installs are disabled
I also noticed the following. The error says "The computer '123.123.123.123' preference item in the Group Policy object ... etc" The IP mentioned in that error is NOT the computer/client running the GPO but the IP address of the target printer.
So the client thinks the Printer already exists or the IP is already taken (or something of that sort).
Here is the GPresult XML for this
<GPO>
  <Name>Printers - deploy - user</Name>
  <Path>
    <Identifier xmlns="http://www.microsoft.com/GroupPolicy/Types">{5C21
1010-F5E0-445C-99F3-0B8A9D9CB680}</Identifier>
    <Domain xmlns="http://www.microsoft.com/GroupPolicy/Types">mydomain.com</Domain>
  </Path>
  <VersionDirectory>34</VersionDirectory>
  <VersionSysvol>34</VersionSysvol>
  <Enabled>true</Enabled>
  <FilterId>MSFT_SomFilter.ID="{6272C5C1-9C4E-40B7-BD5A-277ED70B337D}",Domain="mydomain.com"</FilterId>
  <FilterName>Any Win Desktop OS</FilterName>
  <IsValid>true</IsValid>
  <FilterAllowed>true</FilterAllowed>
  <AccessDenied>false</AccessDenied>
  <Link>
    <SOMPath>mydomain.com/Configuration/Sites/MainOffice</SOMPath>
    <SOMOrder>3</SOMOrder>
    <AppliedOrder>1</AppliedOrder>
    <LinkOrder>4</LinkOrder>
    <Enabled>true</Enabled>
    <NoOverride>false</NoOverride>
  </Link>
</GPO>