HP 48G: How to fix the “Warning: Invalid Card Data” problem

Recently, my good old HP 48G calculator (one of the best calculators ever built and my longtime personal favourite till today) started displaying the following message whenever I switched it on:

Warning: Invalid Card Data

Which seems a bit odd at first, considering the 48G model has no card slot (only the 48GX model has one). Luckily, there’s a simple solution: Execute the PINIT command by typing “PINIT” (without the double quotes) and pressing the ENTER key.

There’s a great, detailed explanation of this problem and the according fix in the “invalid card data at my hp48g” thread over at the independent HP calculator museum. If this warning message appears on a HP 48GX and the problem persists after applying this fix, take a look at step 3 described in the  article titled “Message, Invalid Card Data, is Displayed when the Calculator is Turned On” on HP’s support forum.

Wouldn’t it be a pity if a company with such a great history and so many great hardware products ceased to be a hardware company?

3 Replies to “HP 48G: How to fix the “Warning: Invalid Card Data” problem”

  1. Daniel, Thank you for the answer to my issue and thank you for posting it. I still use mine as well. I do get an insufficent memory though as I have a 128K card added. Happened after I changed my batteries. Got any suggestions?

  2. Hello,
    I also have this problem, but with a HP50g. Unfortunately, when I execute PINIT, in my calculator the word “NOVAL” appears and nothing happen. What could I do?

    1. Hi Raúl,

      unfortunately, I don’t know for sure what to do as I never experienced this error on my HP 48G and don’t have the HP 50G. I did find the following document though:


      According to that, NOVAL just seems to be a regular status shown when no object has been returned by a command:

      “You also see MENU(12) and NOVAL in the main display area. MENU(12) is the command you typed. NOVAL is the result of typing the command. The ‘MENU’ command gives no object as a result, so the HP 50g displays NOVAL to warn you that no object was returned by the command. If you are using RPN mode instead of Algebraic, you type 12 first, press , then type MENU and press again. The hyperbolic functions menu is shown and nothing is put on the stack.”

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