To set IUSR permission for a domain, you must know what IUSR is for the particular domain. To find out the particular IUSR for the particular domain. Follow the steps:
IIS -> Domain -> Properties -> Directory Security -> Authentication and access control -> Edit -> Authentication methods: Here you can find the IUSR name in the username area. ex: IUSR_690
Server application unavailable error: Permissions missing on domain folders can lead to this error.
IIS -> domain -> right click and open -> Properties -> Security:
> Add Asp.net (aspnet), Network service
> If still not working, Add application pool user permission to the domain. To know the application pool user, IIS -> domain -> right click -> properties -> directory settings -> application pool -> note the pool name.
> Now IIS -> application pool -> right the particular application pool -> properties -> note the name.
> Now give permission for that particular user to the domain.
> If still gives the same error, give IUSR permission to the domain. Follow step 1 to do this.
My computer- > manage -> users and groups -> check whether the particular FTP user is disabled or not.
If you still encounter errors, check event viewer
If domain asks for username and password to browse it,
1. Open IIS -> properties -> Directory security -> Authentication and Access control -> Edit -> Authentication methods -> Change the IUSR password in the 2nd text box.
2. My Computer -> right click -> Manage -> Computer management -> Users and groups -> Find that IUSR -> Right click and set the new password
Note: If the user is disabled, enable it.