Unexpected Error: Couldn't load the model schema

Upon trying to connect to an SQL Server database using DirectQuery, I encountered an Unexpected Error: Couldn't load the model schema. I had read some of the solutions such as removing the :port number when entering the server name but it doesn't work for me.

I have attached the log below and would appreciate help on how to resolve the error. Many thanks in advance.

Feedback Type:
Frown (Error)

Timestamp:
2018-11-19T01:52:19.8854494Z

Local Time:
2018-11-19T09:52:19.8854494+08:00

Session ID:
b16c5674-d2e3-4e20-b0bc-624e7767bbfb

Release:
August 2018

Product Version:
2.61.5192.601 (18.08) (x64)

Error Message:
Couldn't load the model schema.

OS Version:
Microsoft Windows NT 10.0.16299.0 (x64 en-US)

CLR Version:
4.7 or later [Release Number = 461814]

Peak Virtual Memory:
34 GB

Private Memory:
591 MB

Peak Working Set:
740 MB

IE Version:
11.248.16299.0

User ID:
df827a11-f3e8-47d5-8d0f-9050e1429ce7

Workbook Package Info:
1* - en-SG, Query Groups: 0, fastCombine: Disabled, runBackgroundAnalysis: True.

Telemetry Enabled:
True

Model Default Mode:
DirectQuery

Snapshot Trace Logs:
C:\Users\rychang\AppData\Local\Microsoft\Power BI Desktop\FrownSnapShot2112601426.zip

Performance Trace Logs:
C:\Users\rychang\AppData\Local\Microsoft\Power BI Desktop\PerformanceTraces.zip

Disabled Preview Features:
PBI_shapeMapVisualEnabled
PBI_newFromWeb
PBI_SpanishLinguisticsEnabled
CustomConnectors
PBI_variationUIChange
PBI_canvasTooltips
PBI_PythonSupportEnabled
PBI_showIncrementalRefreshPolicy
PBI_compositeModels
PBI_DB2DQ

Enabled DirectQuery Options:
PBI_DirectQuery_Unrestricted

Disabled DirectQuery Options:
TreatHanaAsRelationalSource

Cloud:
GlobalCloud

DPI Scale:
100%

Supported Services:
Power BI