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Calc Frequently Asked Questions

Many people have asked questions about Calc, how it came about, etc. Here are answers to some of the most common ones.

General Questions

  1. Why was Calc created?
  2. Why have you released a free version of Calc?
  3. Who are Flow Simulation?
  4. Who uses Calc?
  5. Calc is great. What can I do to help?
  6. What's the difference between the free version of Calc and the paid version?
  7. How do I get a copy of the latest (premium) version?
  8. What are Flow Simulation's contact details?
  9. Is Calc Y2K compliant?

Licensing Issues

  1. How do I register?
  2. The Web form doesn't work/I don't have access to WWW - how do I register?
  3. Why should I register?
  4. What does registration cost?
  5. What happens after 90 days?
  6. Can I really download this program and use it for free for as long as I need it?
  7. Why do you ask for personal information, if the product is free?
  8. I'm not giving you my details. What are you going to do about it?
  9. If I upgrade do I need to register again?
  10. Can I edit my details online?
  11. What are the terms for site licensing?
  12. What will happen to the details I supply when registering?
  13. I have purchased Calc on CD/paid download. Do I still need to register?
  14. Can I obtain the source code of Calc?
  15. Is it okay to include a link to Calc on my personal home page?
  16. Is it okay to include a link to Calc from our organization's web site?
  17. I would like to redistribute Calc. Is this okay?
  18. I would like to unofficially "mirror" Calc on my home page. Is this okay?
  19. Do you have a logo for Calc I could use as the link?
  20. Can I distribute Calc along with my software product/collection?
  21. Can we include a customized version of Calc as part of our software?
  22. I am a professional journalist. How do I get a media kit?
  23. I work for a magazine publisher. May we include Calc on our cover CD?
  24. How do I obtain technical support?


  1. How do I download and install Calc?
  2. Why doesn't Calc have a 'proper' Windows install program?
  3. Will installing Calc unleash some bug that will crash my system?
  4. Where is the Help file?
  5. How do I replace the Windows Calculator with Calc?
  6. Another program starts the Windows Calculator. How do I get it to run Calc instead?
  7. How do I get the calculator icon to appear on my desktop?
  8. Why does my browser window fill with garbage when I try to download factory.prp?
  9. Where does Calc store its files?
  10. Why does Calc use the Windows Registry?
  11. What Windows Registry entries does Calc use?
  12. Why are you using HTML Help?
  13. Why does Calc try to use Internet Explorer?
  14. Why does a file called "default.dat"' keep appearing on my desktop?
  15. Why does a file called "default.dat"' keep appearing in my Start Menu?
  16. How do I get back to the installation prompt to add a shortcut?
  17. I have just upgraded Calc. Why does it look and behave like the old version?
  18. Why does it try to extract the files every time I try to run it?
  19. How do I un-install Calc?
  20. Why do I get an error message that it can't unpack the files when I try to install on Windows?
  21. Does Calc run on 64-bit versions of Windows?

Software Development and Availability

  1. How frequently is Calc updated?
  2. Which Windows operating systems does Calc run on?
  3. Is there a version of Calc for Windows CE (Pocket PC)?
  4. Is there a version of Calc for the Casio BE-300?
  5. Is there a version of Calc for 16 bit Windows (e.g. Windows 3.1)?
  6. Is there a version of Calc for Linux?
  7. Is there a version of Calc for Unix, BSD etc.?
  8. Is there a version of Calc for Palm?
  9. Is there a version of Calc for Psion (EPOC)?
  10. Is there a version of Calc for Apple Macintosh?
  11. Can I install Calc on a WindowsCE device connected to an Apple Macintosh?
  12. What happened to the extra fonts in Calc95, e.g. Buttons, Sevenseg and Minitron?
  13. Why is Calc limited in exponent to 1e300 and 15 digits precision?
  14. Are you planning to develop a version for the Apple iPhone?
  15. Are you planning to develop a version for the RIM Blackberry?

Solutions to Common Problems running Calc

  1. Can I get rid of the Flow Simulation splash screen when Calc starts?
  2. Why can't I use the computer keyboard instead of clicking with the mouse on the buttons?
  3. Could you please provide a list of the keyboard shortcuts?
  4. How do I make the button legends bigger?
  5. How do I make the display bigger?
  6. Where are Calc's statistics functions?
  7. Where are Calc's financial functions?
  8. Where is the pi button?
  9. Where is the percent button?
  10. How do you get mode selections to be the default mode?
  11. How do you get the button size to stay at a given size?
  12. How do I view the stack in RPN mode?
  13. Where is the button to exchange X and Y in RPN mode?
  14. Why, after using for a while in RPN mode, do I get a stack full message?
  15. Where is the button to move the stack down in RPN mode?
  16. Why do the trigonometric functions give inaccurate values (e.g. sine of 10 degrees gives -0.5440211109)?
  17. Why do the trigonometric functions give inaccurate values (e.g. sine of 10 degrees gives 0.156434465)?
  18. How do I clear the Memory?
  19. Is there a way to get Calc to put the decimal point in automatically (like an adding machine)?
  20. How do you change the decimal point symbol?
  21. How do you change the thousands separator?
  22. Why, if I enter "1 + 2 x 3 =" do I get 7 and not 9?
  23. Why is the value truncated to two significant figures when I try to calculate a monthly interest rate?
  24. Why does Calc minimize after a period of inactivity?
  25. Why do I get a message "Unable to open properties database" when I start Calc?
  26. Why do the HEX input keyboard shortcuts A-F only work with the keyboard shift?
  27. Why do I get incorrect results after performing division in HEX mode (or other integer mode)?
  28. Why do am I getting the message "No Data" in the display?
  29. How do you input times in hr/min/sec?
  30. Why am I getting odd fractions denominators in feet/in mode?
  31. Why don't the depreciation functions work as shown in the manual?

Solutions to Common Problems running with Windows

  1. I can't get Calc to show unless it is maximised - what do I do?
  2. When I click on Help in the calculator, why is the page not found?
  3. Why does my computer freeze up when I am running Calc (or other program)?
  4. Why does my computer keep crashing with a Fatal Exception error (blue screen)
  5. Why am I getting the message Exception: 0xC0000005?
  6. How can I get rid of Windows crashes, hangs and freeze-ups?
  7. Why do I only get the digits before the decimal symbol of the number when I try to paste into Calc from another application?
  8. Why do I only get the first digit of the number when I try to paste into another application?
  9. Why do I sometimes get a Windows error after starting in RPN mode?
  10. How do I un-install Calc from my PC?
  11. How do I stop Calc from starting up every time I start the computer?
  12. Why does Calc sometimes hang, e.g. when I click on the '=' key?
  13. Why does Calc look funny on Windows Vista?

Solutions to Common Problems running with Windows Mobile (Pocket PC)

  1. Why do I only get a very limited set of units conversions on Windows CE?
  2. Why can't I save new units and properties on Windows CE?
  3. How do you change the interest rates on Windows CE/Pocket PC?
  4. Why does the input panel sometimes disappear on Pocket PC?
  5. How can I close Calc?
  6. Why is there no Close button or menu item on Pocket PC?
  7. How do I get rid of Calc from the Start menu?
  8. How do I get rid of the second Calc icon in Programs on Windows Mobile 2003?
  9. Why do the menu captions go funny on Pocket PC 2002?
  10. Why do I get strange characters for the divide and multiply buttons?
  11. Why do I get "No Display Data" in the display?
  12. Why is the device giving message Exception: 0xC0000005?
  13. How do I un-install Calc from my device?
  14. I pressed the "cnv>" button - why I can't close Calc?
  15. Why does my Pocket PC freeze up when I try to close Calc using Battery Pack 2003?
  16. Why does version 5.6 not work on the HP-720?
  17. How do I switch on the sound at the end of a countdown in Time mode?
  18. How can I run Calc 5.3 on a square display device such as the HP 6515?
  19. In version 5.67 why doesn't help work?
  20. I installed Calc but later my PDA [died/hard reset/was lost]. How do I install it again?
  21. Can Calc run on Windows Mobile 2003 SE or later devices supporting landscape mode?

Reporting Problems

  1. How do I get units and conversion factors added to Calc?
  2. How do I get physical constants or physical properties added to Calc?
  3. How do I correct erroneous values for conversion factors or constants?
  4. How do I report a bug in Calc?
  5. How can I suggest an enhancement to Calc?
  6. I emailed with a request for help; why didn't you reply?
  7. Why did I get this weird email from you?

Miscellaneous Questions

  1. Why am I getting 743559489.4000000059 instead of 743559489.4?
  2. Why do you get (e.g.) 12.3499999999999943 if the display precision is set to 16 digits, but 12.35 for 12 digits?
  3. If I put in 19.4, it changes that to 19.3999999999999985. Why?
  4. Is Calc capable of doing fractions?
  5. Why don't you have a scrolling tape?
  6. Can Calc calculate exchange rates?
  7. How do I bring up the Periodic Table of Elements?
  8. How would I calculate a percentage of change?
  9. Why is a Calc's keypad upside down when compared with a telephone keypad?
  10. Why doesn't Calc have a conversion from teaspoons etc. to ounces?
  11. Why is your value for conversion to Btu incorrect?
  12. How do I calculate the rate of compound interest?
  13. How do I calculate a logarithm to a base other than 10 or e?
  14. Is the degrees API/Baume conversion correct?