@Peter Clift (INFOSYS LIMITED) Thank you for reaching out to Microsoft Q&A. Apologize for the inconvenience caused on this.
As @Anonymous mentioned, Currently Azure DeVops is not supported over the Microsoft Q&A, I would suggest you report your problem in Azure DeVops developer community
According to this document, the error is caused by that Web Deploy cannot connect to the remote service. Please refer to the follow points to troubleshoot your problem:
- Please make sure Azure app service works fine.
- That the msdepsvc(“Microsoft Web Deployment Agent Service”) or wmsvc(“Web Management Service”) service is started on the remote server.
- Your firewall is not blocking incoming connections of your ports on the destination. If you used the default installation, then it would be 80 for msdepsvc and 8172 for wmsvc.
In addition, you could try to add -retryInterval:6000 -retryAttempts:10 to Additional Arguments in Azure App Service Deploy task as suggested in the similar thread.