I recently upgraded to PowerCLI 11.3 and started running into the same issues with "Unable to connect to the remote server". I thought it was related to 11.3 in particular, but when I went to the Module folder for SRM, I had two folders, one for a Version 10.x and one for 11.2
Get-Module VMware.VimAutomation.Srm -ListAvailable | Select ModuleBase
I went to the entire Module folder and deleted all of the VMware folders and installed the 11.0 version as a test
Install-Module -Name VMware.PowerCLI -RequiredVersion 11.0.0.10380590
With this I was able to connect to both SRM sites without error. I then upgraded through each release version and it continued working. I think ultimately there was a conflict with the two folders in the VMware.VimAutomation.Srm module folder and manually deleting all of the VMware modules and installing only the latest resolved the issue for me on two different computers.
