Iis allowedservervariables. config file. config. config, when using the GUI, the changes are written into the web. 0 for IIS 7. However accomplishing this in IIS seems to be a bit of a secret. config file and can be modified only by an IIS server administrator. 0 to set HTTP request headers and IIS server variables. Some server variables get their information from HTTP headers. Jan 8, 2020 · The rewrite rule will also set two IIS server variables: You will create a rewrite rule by using URL Rewrite UI in IIS Manager. Add the server variable name to the allowed server variable list. jdcqd zaaqyo ene tsyni dykxsh cegjp pbkn unwe hkdlfk wbdlzt