For the VNI #311 error, you should try to run the LNS Database validation tool. Customers also reported the error was fixed after running scandisk.
If we assume the error is actually VNI #310, then it is possible some LNS limits are met. For example, there is a default limit of 8000 NvMonitorPOints and this is typically the first to be reached
The number of monitor points is controlled by a registry key
HKEY_LOCAL_MACHINE\SOFTWARE\LonWorks\VNI\Global\Max Private Nvs HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\LonWorks\VNI\Global\Max Private Nvs (64-bit OS)
Start the TestVNI application in your LonWorks\bin folder. Select the network and click properties. The Max Private NVs is in the bottom part on the left. Change the value to 16000 and click OK.