ProgIDs are the human-readable equivalent of Microsoft [COM] [CLSID] values. There is a Win32 API to convert from one to the other (ProgIDFromCLSID). ProgIDs are what you pass to scripting applications to create COM objects. Is this the "application name" [tcom] needs? Yes. Example values: InternetExplorer.Application package require tcom set ie [tcom::ref createobject "InternetExplorer.Application"] $ie Visible 1 $ie Navigate http://www.tcl.tk/ ---- See also "[registry]". <> Windows