Is a 64 GB Flash Drive Compatable?

After inserting the drive, open Disk Utility (Applications > Utilities) and highlight the drive (as shown here in this screenshot of my internal drive) - your flash drive should who underneath your internal drive:

At the bottom, my drive shows as being formatted as Mac OS Extended.

So, does yours show up on the left

And how is it formatted?

Nope, the secure access feature can be duplicated by Apple's own Disk Utility which allows you to create your own AES encrypted disk image to store data on. If encrypting your data on the Flash drive is what you want. And before reformatting it, copy all the data of your own back to the Mac. Otherwise you'll lose that data. This tip explains what the different formatting will do for compatibility, and link to a tip on installing Windows as well.

https://discussions.apple.com/docs/DOC-3003

But you have to make a choice here, how transportable your data is. Read this tip thoroughly and choose the formatting you want. FAT32 won't give you full access to the 64GB. But ExFAT will, NTFS will (if you add an NTFS writing plugin to your Mac), and so will HFS+: Apple's encryption only works if you only use HFS+ and never use Windows.

Sansdisk .exe is useful if you just want to use it in Windows only environment. You may want to contact Sansdisk to discover if their Mac software supports both platforms or not. If it doesn't then it really doesn't matter.

The memory capacity of the flash drive is irrelevant - you can attach 500 GB drives. Not sure why it would not be recognized - when you opened Disk Utility, did the drive show at all in the left column?

And, do you have your Finder Preferences set to show external drives on the desktop?

On another subject: I see you have the bare minimum 2 GB of RAM running Mountain lion - how has your Mac been performing? Aside from the current problem, I would strongly suggest that you check into getting more RAM - yours should be able to handle 8 GB, so I'd suggest at least upgrading to 4 GB RAM.

I don't see where that would be a problem, since my iMac 5,1 a 32 bit machine could see a 2 TB hard drive externally formatted for a Mac OS. Although perhaps the operating system that formatted the drive needs 64 bit RAM capacity to work at 64 bit. Many Flash drives use NTFS or ExFAT because the old FAT32 only supported 2 GB. It is worth trying to see if it works. 4 GB is the maximum of 32 bit addressing. Mac OS X may switch between 32 bit and 64 bit readily but the formatting may not be as flexible.

3) Is it difficult for me to install 4GB Ram? (I am not computer savvy re installing things).

No. It is quite easy. Is this your model:

http://everymac.com/systems/apple/imac/specs/imac-core-2-duo-2.66-20-inch-alumin um-early-2009-specs.html

You can check here:

http://eshop.macsales.com/shop/memory/iMac/DDR3_2009

And, if you click on the tech support tab at the top of the page and then on install videos, you can choose your model and watch a how-to video.

4) Would 4GB Ram help my IMac to recognize a 64 GB Flash Drive?

Not that I know of (or at least not sure). I believe a brody might have hit it on the head: if your drive can only address 32 bit, then I'm not sure how to overcome that - Mountain Lion will only address 64 bit. Frankly, I do not know if it changes to 64 bit once you reformat it for a Mac?

You need to reformat the drive. You don't need anything that is on it currently - unless you also want to use it with Windows (which I cannot help with since I do not run Windows).

Highlight the SanDisk drive in the left column in Disk Utility.

Click on the Partition tab.

Choose 1 Partition.

Choose a name ("backup") and type it in

Under Format, choose Mac OS Extended (Journaled)

Click on Options and choose GUID Partition scheme

Click on Apply

When finished, the drive is ready to use.

As I said, you do NOT need any program or any .exe file (which is a Windows file and won't work on a Mac anyway). You also don't need a second icon - your drive has one partition, so you have one icon. Your 32 GB drive simply has the preinstalled Windows stuff on it - you can get rid of that by following the same steps - however, be aware that this will erase all the contents, so you'd lose everything on it.

I have three large external hard drives, 6 or 7 flash drives, 2 smaller portable hard drives, and an external burner. Everything has been formatted properly for Macs and only shows 1 icon each unless I partition a hard drive into, say, 3 partitions - then I will have three icons for that drive.

What if I do nothing with the SanDisk 32GB flash drive. It still has the preinstalled Windows stuff on it. It still has all my photos on it. Can I keep it as is, with the WIndows stuff on it? Or will having the WIndows stuff on it eventually cause problems?

Since it's worked so far, it should be ok. I don't know if it can cause problems later since I don't run anything Windows, so I'm not familiar with it.

If you want to change formatting, a brody gave you all the options. If you reformat, that will wipe your contents - so you would have to temporarily move your files elsewhere and then move them back.

And thanks, a brody, for the explanation on the locked icon - being unfamiliar with Windows, I did not know that.

Are you taking about a SD card and you are putting it in the SD Reader, Slot, on the side of the Mac? If so then NO it is not supported. Those cards are eXtended Capacity, XC, and the reader on your Mac does not support that type of card.

You can get a external SDXC card reader almost anywhere that will support it. It would connect to your Mac by USB cable. Or you may find one that work with FireWire.