I hope you found the resolution. 

But if not, there are several articles in the Sage Knowledgebase (https://communityhub.sage.com/global-resources - select Country & Sage 100 product) addressing this error, that might be helpful regarding that error.

Some issues you may want to review:

Windows Firewall or similar blocking accessing to that Sage 100 integration engine port (default is 8888, with service being Disabled initially until you make active) either on the Sage 100 server or the CRM Server.

Confirm the Sage CRM SQL Server Logon Password field in CRM Server Options in Sage 100 (Sage 100 - Customer Relationship - Main - CRM Server Options - Sage CRM SQL Server Logon - Logon field)- this password may have changed, or user is Locked out.

Additionally, the Sage 100 Logon specified for the integration on CRM Server Options may have had their password changed in Sage 100 or is locked out.  (If that user's password has changed, there is not a Password field on the CRM Server Options so select another Sage 100 User Logon, Accept the change, change it back to the original Sage 100 User Logon, and Accept, and the latest password will pull from User Maintenance settings - if a password was entered there).

To assist in troubleshooting, try running the Sage 100 Integration as an Application (temporarily) instead of a service and it will often display details regarding the communication attempt when you select Load Sage CRM Data from the CRM Server Options in Sage 100 (essentially create a shortcut on the desktop to run command from service but without the -service flag, then launch this shortcut and send the synchronization request Load Sage CRM data from CRM Server Options screen in Sage 100 and see if details display if it fails - if no attempt noted, no response and no error it is even more likely to be a Firewall or something blocking the communication).

Sage Knowledgebase article on How to run the Sage 100 Integration Engine for Sage CRM as an application on the Sage 100 server:

https://us-kb.sage.com/portal/app/portlets/results/viewsolution.jsp?solutionid=222924950026987&fromemail=true

Finally, check the CRM Activity Log in Sage 100 for errors detailing issues such as login issues, SQL related issues including duplicate key, or permissions errors (Sage 100 - Customer Relationship Management - Main - CRM Activity Log

I hope you found the resolution. 

But if not, there are several articles in the Sage Knowledgebase (https://communityhub.sage.com/global-resources - select Country & Sage 100 product) addressing this error, that might be helpful regarding that error.

Some issues you may want to review:

Windows Firewall or similar blocking accessing to that Sage 100 integration engine port (default is 8888, with service being Disabled initially until you make active) either on the Sage 100 server or the CRM Server.

Confirm the Sage CRM SQL Server Logon Password field in CRM Server Options in Sage 100 (Sage 100 - Customer Relationship - Main - CRM Server Options - Sage CRM SQL Server Logon - Logon field)- this password may have changed, or user is Locked out.

Additionally, the Sage 100 Logon specified for the integration on CRM Server Options may have had their password changed in Sage 100 or is locked out.  (If that user's password has changed, there is not a Password field on the CRM Server Options so select another Sage 100 User Logon, Accept the change, change it back to the original Sage 100 User Logon, and Accept, and the latest password will pull from User Maintenance settings - if a password was entered there).

To assist in troubleshooting, try running the Sage 100 Integration as an Application (temporarily) instead of a service and it will often display details regarding the communication attempt when you select Load Sage CRM Data from the CRM Server Options in Sage 100 (essentially create a shortcut on the desktop to run command from service but without the -service flag, then launch this shortcut and send the synchronization request Load Sage CRM data from CRM Server Options screen in Sage 100 and see if details display if it fails - if no attempt noted, no response and no error it is even more likely to be a Firewall or something blocking the communication).

Sage Knowledgebase article on How to run the Sage 100 Integration Engine for Sage CRM as an application on the Sage 100 server:

https://us-kb.sage.com/portal/app/portlets/results/viewsolution.jsp?solutionid=222924950026987&fromemail=true

Finally, check the CRM Activity Log in Sage 100 for errors detailing issues such as login issues, SQL related issues including duplicate key, or permissions errors (Sage 100 - Customer Relationship Management - Main - CRM Activity Log