This may be an issue that is outlined in the Knowledgebase. You may want to call support. The article ID of this article is 31388. There are links to some additional articles when you view it through the Knowledgebase
In your case look at Option C: Version 14.1 and higher.

Error: "A newer version exists on the server" (SIM Registry Key)

Products
Sage 300 CRE

Description
You may see Error: "A newer version exists on the server" when attempting to launch TS-Main or Sage Desktop even though no updates have been applied recently and your workstation was previously working properly.



Cause
The Sage Installation Manager Server is updating the Accounting SIM Server Version registry key in error. Sometimes this is caused by migrating to a new server and leaving the SIM Server service running on the old server.

Resolution
Ensure the Accounting Sim Server Version value in the registry is updated.

Option A: Restart the Sage Installation Manager Server Service.

From the Windows Start menu, select Search and enter Services.msc
Right-click on the Sage Installation Manager service and select Restart.

Option B: (Version 13.1 and below only) Manually update the Accounting SIM Server Version value in the registry:

Obtain the correct version from a working workstation by checking the value for:
Windows 32bit:
HKEY_Local_Machine\Software\Timberline\General\Accounting SIM Server Version
Windows 64 bit:
HKEY_Local_Machine\Software\WOW6432node\Timberline\General\Accounting SIM Server Version
Change the registry value on the workstation that is getting the error.
If you are unable to locate the Accounting SIM Server Version from a working computer, you can find it in the ProductManifest.xml file:

Browse to C:\ProgramData\Sage
Open ProductManifest.xml in Notepad
Click Edit, Find and search for "SIMManagedProducts"
Note the Version value for SIMManagedProduct Name="Accounting"
Replace the Accounting SIM Server Version value in the ...Timberline\General\ key with that value


Option C: Version 14.1 and higher

If the version listed in the error message is lower on the server than on the workstations, you may need to update a file on the server.

Ensure the update was applied at the server
WARNING: If the patch logs or EXE file properties do not confirm the update was applied successfully on either the server or the workstation(s), do NOT apply this fix. This fix is only intended in cases where the patch update successfully applied on the server, but the ServerVersion.xml file was not updated correctly.
Browse to C:\ProgramData\SAGE\TIMBERLINE OFFICE\9.5\ACCOUNTING
Right click serverversion.xml and choose Edit
Change the value for <stoaccounting Version="00.0.00.00.0" /> to match the version displayed for the workstation. See "
Error: "A newer version of Sage 300 Construction and Real Estate has been installed on server." (new or applied update for 14.1 or 15.1)" in Related Resources below for more information on this issue.
For more Help: Chat with Support



Related resources
Error: "A newer version exists on the server" after installing 13.1 on workstation
Error: "A newer version of Sage 300 Construction and Real Estate has been installed on server." (new or applied update for 14.1 or 15.1)
Additional information
If this is happening after a recent server migration and upgrade, and the old server is still being used on the network, the SIM Server service is still running on the old server.

You will need to either uninstall Sage from the old server. Or all Sage services on the old server need to be stopped and disabled so the Sage SIM service is not broadcasting outdated information



Category
Product update

Entitlement
Open



ID:31388 Last Modified Date:4-1-2016

We had this issue with the year end update we run 15.1, support talked me through it, basically you log into your server, open timeberlineOffice/Accounting/9.5/ServerVersion- this is an XML document open it with notepad or something similar change the number sequence of the version to match the version on the workstation--took maybe 3 minutes

You're a lifesaver. That was it.

You are welcome