Issues with website without web.config
SolidCP cannot update or remove a website without web.config file.
I suggest can to remove a website without web.config or recreate a default web.config file to update or remove a website.
Which IIS version do you use?
As in general non-existing web.config in IIS 8 and above gets re-created without errors (by just pressing save on the Website Properties).
Only if the web.config is wrongfully formatted or uses unrecognizable strings it errors out.
If there's no web.config it re-creates it.
I have followed your steps. The web.config is re-created it successfully when the folder usernamedomain.comwwwroot exists. But when the folder NOT exists then web.config cannot be created.
I suggest to add a button in Website properties called "Reset Website" and create a folder usernamedomain.comwwwroot and the web.config and default.aspx per default as reset factory settings.
I can confirm this issue and have already tracked it as issue in git: https://git.key4ce.com/SolidCP/v2.x/issues/2
If the folder does not exist IIS Management aswell as SolidCP will error out in website properties yes.
But it also means the reset button as per example needs to be at a higher level (for example in websites list) or automatically re-create if it doesn't exist.
in either case this would be a new feature and not so much a bug though (same as it's listed as enhancement in git).