If your Dynamics NAV or Dynamics 365 Business Central Windows Client does not start after a windows update, be sure to look inside Event Viewer Application Log and see if you find a stack trace like the following
Type: Microsoft.Dynamics.Nav.Types.Exceptions.WatsonReportException
Message: <ii>Watson report failure</ii>
StackTrace:
bij Microsoft.Dynamics.Nav.Watson.WatsonHandler.SendWatsonReport(Exception exception, Boolean showUI, Assembly assembly, String applicationName)
bij Microsoft.Dynamics.Nav.Client.WinClient.StartWinFormsClient.HandleWatson(Exception exception, Int32& runCore)
Source: Microsoft.Dynamics.Nav.Watson
HResult: -2146233088
----------------------------------
Type: System.NullReferenceException
Message: <ii>De objectverwijzing is niet op een exemplaar van een object ingesteld.</ii>
StackTrace:
bij Microsoft.Dynamics.Nav.Client.WinClientExcelExportService.FindMajorVersion(RegistryKey registryKey)
bij Microsoft.Dynamics.Nav.Client.WinClientExcelExportService.<.ctor>b__8_0(RegistryKey regKey)
bij Microsoft.Dynamics.Nav.Client.WinClientExcelExportService.FindRegistryKey(RegistryHive hive, String keyName, Action`1 action)
bij Microsoft.Dynamics.Nav.Client.WinClientExcelExportService.FindFirstRegistryKey(String keyName, Action`1 action)
bij Microsoft.Dynamics.Nav.Client.WinClientExcelExportService..ctor(UISession uiSession)
bij Microsoft.Dynamics.Nav.Client.WinClient.NavWinFormsClientSession.<>c.<AddServices>b__22_6(UISession uis)
bij Microsoft.Dynamics.Framework.UI.ClientSessionCore.AddUIService(Func`2 addService)
bij Microsoft.Dynamics.Nav.Client.WinClient.NavWinFormsClientSession.AddServices()
bij Microsoft.Dynamics.Framework.UI.ClientSessionCore.Prepare()
bij Microsoft.Dynamics.Nav.Client.WinClient.StartWinFormsClient.SetupClientSession()
bij Microsoft.Dynamics.Nav.Client.WinClient.StartWinFormsClient.RunCore()
Source: Microsoft.Dynamics.Nav.Client.WinClient
HResult: -2147467261
SOLUTION
This event should have happened right after a Windows update and Dynamics NAV / Dynamics 365 Business Central client is a victim of this.
Some registry keys getting lost with that, unfortunately, which the application needs as it is checking during client startup if Microsoft Excel is installed and e.g. which version has been deployed.
To resolve this problem, you have to verify that these registry path and keys exists
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\excel.exe
@="C:\\Program Files\\Microsoft Office\\Root\\Office16\\EXCEL.EXE"
"Path"="C:\\Program Files\\Microsoft Office\\Root\\Office16\\"
"UseURL"="1"
"SaveURL"="1"
If these are not existing, you have to add them manually or through a .reg file. (NOTE: these are related to Office16).