HP 50G Can't Format SD Card or Store on SD Card

[mark4flies]

I bought a new HP 50G calulator a couple of months ago. It came with the lastest hardware and software. I researched problems using the SD card feature. This older calculator seems to be unable to use newer SDHC cards or SD cards with storage capacity above 2 GB. Many reported no problems with cards sizes up to 2 GB. I ordered two brand new 2 GB SD cards. I tried to format them in the calculator but I got the error message, "Disk Protected." I tried to store a variable and got the same message. The same result occured with both cards.

I then ordered two new 1 GB SD cards thinking that the initial cards were too big. I got the same result. The calculator is otherwise operating perfectly and passes all tests. It can read the cards. I was able without any trouble to format all the cards with both a Windows 7 computer and a macOS Sierra computer with FAT16, store a couple of text files, and then read these on the calculator. I just can't write to the cards with the calculator.

The lock switch on the side of the SD card is off on all four of the cards.

Does anyone have a suggestion?