I am trying to encrypt a web.config file using the following command i am getting the error like below: "Illegal characters in path" aspnet_regiis.exe -pef "connection Strings" "D:\Password Encryption\DPAPITestWeb\DPAPITestWeb\" prov "DataProtection ConfigurationProvider" web.config section has been provided below : could encrypt this in different machine. But only this issue arrises on my machine.