About Virtlab
Carl Spitzweg (1808-1885) "Der Alchemist"

 Virtlab Demonstration
Pietro Longhi (1701 - 1785) "The Alchymist"

Most problems with Virtlab arise because of browser settings or differences between browsers. The information below will help you solve most problems. If, however, you believe you have found a bug in our software or a problem unrelated to those described below, please contact us at support@virtlab.com.


Virtlab depends heavily upon the nature of your browser. You must enable cookies and Javascript. Even then, some browsers perform better than others (largely because of differences in the Javascript DOM). We have tried hard to support as many browsers as possible and always test against the latest version of Internet Explorer, Firefox, and Chrome. Tests with recent versions of Safari (both Macintosh and PC) have been successful but Opera is not working (see below). We used to recommend that Macintosh users download Firefox for the Macintosh, but are now satisfied that recent releases of Safari will also perform satisfactory.

Visual simulations (the "Laboratory" tab) require a recent version of the Flash Player.

Model building (the "Models" tab) requires an electronic spreadsheet. We developed our models using Microsoft Excel, but most spreadsheets can accept and convert Excel files. Model building is a slightly more advanced part of Virtlab training. We hope you will try it and enjoy it!


Browser Settings: All flavors of cookies (both RAM and disk-based) should be permitted by your browser. This is the default setting for most browsers. We use cookies to maintain continuity between pages and sessions.

Javascript must be enabled. This is the default setting for most browsers. In order to support as many screen resolutions as possible, Javascript is used to create moveable and resizeable windows.

Internet Explorer: Virtlab has been tested against Internet Explorer versions 6 - 8. We have encountered no problems.

Mozilla/Firefox: Virtlab has been tested successfully with Firefox versions 1.5 - 3.5.

Opera: Opera does not work in Virtlab. It will not display our Flash simulations in our "Course" pages. (Oddly, it works fine in our opening page demo.) Opera does not support our Javascript for printing the exercise manual.

Safari: Early versions of Safari had many problems when tested with Virtlab. The coordination between the left- and right-hand scrollbars in the Instruction window were among the most serious. Recent versions of Safari have no such problems.

Other Browsers: We have tried hard to use techniques and libraries that are compatible across many browsers. We do not anticipate that you will find serious incompatibilities with modern browsers (Opera seems to be an unusual exception). Please let us know of any unusual behavior that you encounter.

Flash Plugin

Virtlab Flash simulations were developed using Flash 8 and Actionscript 2.0. It is available for virtually all browsers and is often a default presence in modern browsers. The most recent version of the Flash player is free and is available at http://www.adobe.com

Electronic Spreadsheets

The electronic spreadsheet was once defined by Alan Kaye as a "tissue-like superobject". It is an extraordinarily friendly way of performing "what-if" calculations and it offers you the opportunity to design and explore your own simulations and "thought experiments" in Virtlab. There are many guided exercises of this sort in the "Models" tab of Virtlab. While Microsoft Excel was used to develop the models used in Virtlab you should be able to find other spreadsheet software that supports the Excel file format (use your favorite search engine and look for "spreadsheet software").

Contact Us

You are always welcome to contact us with comments and questions. The email address for Virtlab's editor is dbarkley@virtlab.com