An unfortunate bad first experience. Here are the details for the support group. Installed as myself (admin) on Win 7 platform. Failed to execute: "Chicago Option Pricing Calculator has stopped working." Uninstalled and reinstalled: Run As Admin (just to be sure). Same failure on execution. Here are the problem details provided by the failure message. Problem signature: Problem Event Name: CLR20r3 Problem Signature 01: optionpricingcalculator.exe Problem Signature 02: 18.104.22.168 Problem Signature 03: 4897df20 Problem Signature 04: System Problem Signature 05: 22.214.171.124 Problem Signature 06: 506c18e6 Problem Signature 07: 38ed Problem Signature 08: 116 Problem Signature 09: System.Security.Security OS Version: 6.1.7601.2.1.0.768.3 Locale ID: 1033 I would !really! like to have a working copy of this application. Thanks. H PS I believe it is spelled Option. PSS the support link to SourceForge provided on the page is 404 sourceforge.net/forum/forum.php?forum_id=354544. AND 354544 cant be found on a search on the SF site.. DID I JUST LOAD AND EXECUTE A VIRUS VECTOR? What happened to the usual strong validation by the SF folks on this one?