Event ID - 234

Event Id234
SourceSNA DLC Link Service
DescriptionFailed to open SAP 196, error (43) Some connections may now be unavailable.
Event InformationAccording to Microsoft:
CAUSE:
When you configure a large number of SNA Server DLC 802.2 connections to the same IBM host address, a unique SNA DLC 802.2 link service must be used for each connection, where the local SAP address is incremented by 4 for each link service. For example, the first link/connection uses a local SAP address of 0x04, the second uses 0x08, the third uses 0x0C, and so on. If up to 49 802.2 DLC link services are being used, the local SNA SAP address for the 49th link/connection uses SAP address 0xC4.
However, SAP address 0xC4 is automatically opened by Hpmon.dll when the Windows NT print subsystem initializes, and it cannot be changed. This causes a conflict with the 49th SNA Server 802.2 link service/connection, leading to the above error messages.
WORKAROUND:
There are two possible workarounds for this problem:
• Skip local SAP address 0xC4. Instead of using 0xC4, use the next SAP or 0xC8.
• Disable HPMON, if it is not being used.
The Hpmon.dll file can be renamed so that it is not loaded, assuming the Windows NT Server computer is not supporting DLC-attached HP network printers. Note that TCP/IP attached HP printers are not affected by this module, only DLC attached printers. To disable the Hpmon.dll file, perform the following procedure:
1. Rename <ntroot>\system32\HPMON.DLL to HPMON.OLD.
2. Shut down and restart the Windows NT Server computer.
Reference LinksActivating SNA DLC 802.2 Local SAP 0xC4 Fails with Error #0235

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