Symptoms

You receive the following error when adding or editing an ODX data source:

Error in command: 'Add Data Source...'.
Service request failed: Access is denied
Module: TimeXtender.ODX.Engine
TimeXtender.ODX.Engine.ODXFaultException

Cause

Check to see if a policy in Windows Defender Exploit Guard is blocking an ODX operation.

Troubleshooting

ODX service log may show the following error:

Service request failed:
System.ComponentModel.Win32Exception (0x80004005): Access is denied
   at System.Diagnostics.Process.StartWithCreateProcess(ProcessStartInfo startInfo)
   at DynamicProcessEngine.DynamicProcessClient.StartProcess(String serverName, Boolean x64BitVersion)
   at DynamicProcessEngine.DynamicProcessClient.StartPipelineServer(Boolean x64BitVersion)

Some configuration on this machine is blocking the ODX from starting new processes and communicating with those.

Examine errors and warnings in Event Viewer:

Application and Services Log

Microsoft -> Windows -> Windows Defender -> Operational

Below is an example warning:

Microsoft Defender Exploit Guard has blocked an operation that is not allowed by your IT administrator.
For more information please contact your IT administrator.
ID: 01443614-CD74-433A-B99E-2ECDC07BFC25
Detection time: 2021-11-17T19:36:41.903Z
User: <name>
Path: C:\Program Files\TimeXtender\TimeXtender 20.10.25.64\ExecutionEngine_x64.exe
Process Name: C:\Windows\explorer.exe
......

Resolution

Work with your IT team to review Windows Defender Exploit Guard policies, to whitelist (bypass) TimeXtender and ODX installation folders.

Reference

Windows Defender Exploit Guard policy