The answer to this issue is the card reader driver. I found it by going to this link, then enter your Acer model name eg: Aspire > model # eg: 5610 > then make sure you enter the proper OS in the dropdown.
You will also find most other drivers there as well and till so far, it is free.
Usually the Tools and the Utilities CD should be delivered with your notebook.
On this CD you will find all necessary drivers for Windows Vista.
If you install the drivers so you have to do it in the right order.
Very important is the installation of the chipset utility. This must be done at first.
Additionally you need the cardbus driver for your PCMCIA CardBus controller.
Open device manager and double click on the first pci flash memory and click on driver and then click on update driver and click on search online for it. I had the same problem and it found the drivers and installed automatically.