This normally happens when the number of users logged into MAS90 errr Sage 100 exceeds 15 and you are running it as a Service. The suggested fix is to run it as an application. If you know how to contact him Alnoor Cassim, the Luke Skywalker of all things MAS90 is the one who did most of the research on the topic and who wrote most of the white papers.

Thank you for responding.

They typically have fewer than 10 users connected and it still gives the error intermittently even when running as an application. I was eager to try the registry tweak due to all the publicity on other threads in this forum. There are lots of references to the KB article that explains the registry modification, but no one thought to include the instructions from the article... Without knowing what key to modify, I can't pursue that route.

I will look for Alnoor Cassim or any white papers by him, thanks for the suggestion. If anyone can remember the registry key to modify or knows where I can find this information, your help would be greatly appreciated.

The information below might be helpful from the Sage Knowledgebase at https://support.na.sage.com

I suspect that the old article you are referring to is KB article 20344 which refers to Windows Services and not being able to create a new session with a large number of users. However, those symptoms are: Cannot create a new session with a large number of users, "WindX client connection: Connection Timed Out waiting for your application to start" and/or Blank white screen displays when opening Sage 100 Advanced tasks.

Based on your current error, the article below may be a better article, KB 19875: "Connection failure to host: [TCP] <server>:<port number>: NODELAY: STREAM" occurs when accessing and processing through any task module in Sage 100 ERP.

Cause: The service may be corrupt or another application is using the same port number as Sage 100 ERP.
The root cause is often due to a problem with the network environment. The suggested resolutions are potential workarounds.

Resolution: To resolve these issues, perform the following:

If error occurs with all tasks and the port number in error is random port number from 49152 - 65535 then Program Process Inbound Rules needs to be created on the Windows 2008 or 2012 Server under Windows Firewall Advanced Security.

Open Administrative Tools, Windows Firewall with Advanced Security console
In the left pane of the console, select Inbound Rules
Right-click select New Rule
Select Program click Next
Select "This program path:" and browse to <drive letter>\..\mas90\home\pvxwin32.exe (i.e. C:\Sage\MAS90\Home\pvxwin32.exe) on server
Select Next until get to 'Specify the name and Description of this Rule" screen
Enter name for Inbound Rule
Select Finish
In the left pane of the console, select Inbound Rules
Right-click select New Rule
Select Program click Next
Select "This program path:" and browse to <drive letter>\..\mas90\launcher\launcher32.exe (i.e. C:\Sage\MAS90\Launcher\launcher32.exe) on server
Select Next until get to 'Specify the name and Description of this Rule" screen
Enter name for Inbound Rule
Select Finish

To remove corruption from the Sage 100 service, disable and reinstall the service. Then create new files:

-- To uninstall the Sage 100 ERP service:
From the Windows desktop on the Sage 100 server, click the Start button. On the Programs menu, point to Sage Software, and then click Uninstall Application Server Service.
In the Service field, select the service, and then select the port of the service.
Click the Remove button.
Click Yes to confirm.
To reinstall the Application Server Service:

From the Windows desktop on the Sage 100 server, click the Start button. On the Programs menu, point to Sage Software, and then click Application Server Service Setup.
Select the path to the Sage 100 folder
Click OK to add the service.
Note: The service is added based on the settings on the Server tab of Application Server Configuration.

--- To refresh the Application Server Configuration files in case of corruption and make the connection more stable:

Stop the Application Server and close the Application Server Configuration application.
On the Sage 100 ERP server, rename the following files:
..\MAS90\MAS_System\SY_Console.m4t
..\MAS90\MAS_System\SY_Workstation.m4t
..\MAS90\Home\Lib\_Appserv\Locate.pvk
..\MAS90\Home\Lib\_Appserv\Sessions.pvk
Restart the Application for Sage 100 ERP Advanced or Premium
From the Windows Desktop at the Sage 100 ERP server, click Start
On the Programs menu, point to the Sage Software or Sage program folder
Select click Application Server Configuration
Click the Server tab. Clear the KeepAlives check box
Click the Clients tab. On the Re-Connect list, select None
Note: New Locate.pvk and Sessions.pvk files are created when the Application is restarted. If Sage 100 ERP is normally run as a Service, start the Application first and follow the steps above, then make sure at least one user can log in. Then have that user log out and stop the Application, then Start the Service and allow users to log in.)
If problem continues, consider changing the port number:

At the Sage 100 ERP server, set the service to Manually Start.
From the Windows Desktop on the Sage 100 server, click Start. On the Programs menu, point to Sage Software or Sage program folder, then click Application Server Configuration.
Click the Server tab. In the Sockets field, change the socket number to any unused number between 9,000 and 10,000. (If using a firewall, make sure the port is not blocked.)
Click the Start button
If the service starts and runs as an application on the new port number, remove the previous service, and create a new one with the new port number.
Remove the original service using Uninstall Application Server Service.
Create a new service using Application Server Service Setup
If the message is occuring for Specific users:

--- To Run Sage 100 as an Application rather than as a Service:
On the Sage 100 server from the Windows Taskbar, click Start, Program Files, Sage, Application Server Configuration.
Click Start

KB 20344 Cannot create a new session with a large number of users SS3003-ABC at https://support.na.sage.com (you will need to login) is the new article that has the information from the old article.