I have a problem with my minage z1, every card i put in it says unable to use card the same cards does works in other camera's pc etc

Hi. I think your camera is possibly a Minolta Dimage Z1, and if so two possible reasons for this problem come to mind.

1.) I think the Z1 was available around 2003, which in terms of cameras is quite a long time ago! In those days the cards had a relatively small capacity, commonly just Megabytes, and so the cameras were not designed to take the current crop of cards with much larger capacities, which are usually specified in Gigabytes. There are also newer types of SD card, such as SDHC, which sometimes cannot be handled by older cameras.

A review said about cards "The DiMAGE Z1 stores its images on SD memory cards, and a 16MB card accompanies the camera. (The camera also works with the slightly less expensive MMC cards.) I highly recommend picking up a larger capacity card right away, so you don't miss any important shots. (A 64 MB card represents a good tradeoff between capacity and cost.) Connection to a host computer for image download is via USB."

Therefore I guess you may have tried cards which are not suitable just because they are too big but the camera may be able to work again if you can find a small capacity SD card or Multimedia card.

2.) Another possibility is that the 'format' of the cards you have tried was not suitable. To test this you could try formatting them on a computer by right clicking the card's icon in the 'My Computer' window, to bring up the format options. If the camera can then see them you should reformat them by using the camera's menus.

I hope this helps.