Can't access an ExFat partion on Mac OSX from Windows 7

That is a strange fact of mac-world that you need to live with.

My SL could not make an exFAT acceptable to Windows, but Windows 7 made an exFAT acceptable to my SL.

Unfortunate to find out now that you have so much in your Mac-used exFAT, but know you just need a temporary exFAT disk/partition to hold those files ... maybe a 32 GB thumb drive or an external drive.

I can only tell you that a thumb drive I use for file-share works as exFAT for both when Windows formats it, but Windows fails to read it when OSX formats it.

Cannot explain why, just can say it does.

I hope this helps in some small way.

Incredible. I've just been tackling the same problem, after purchasing a Mac a week ago, and I thought there was something I was missing in my grasp of Mac networking. I am shocked by the degree of incompatibility that still exists between Mac and Windows - Apple advertising emphasizes the smooth interoperability between systems, but it seems to me that things have barely improved since I last owned a Mac Quadra 840AV in the early 1990s. Not only is a modern the Mac unable to write NTFS drives, it cannot share the only file format (exFAT) which can be used on both systems. I guess the only option is to copy all my terabytes of files off the drive, and reformat it as an HFS+ drive. (Windows can read the drive using third-party software.) It's a really bad solution, though.

I doubt that the problem is linked to the TimeCapsule, because I don't have one, but I am experiencing what appears to be the same problem accessing exFAT drives. My setup uses an Ethernet network and a Netgear router. My exFAT drive was formatted on a Windows 7 system, and works fine locally on the Mac, but attempting to connect to it from a Windows system just gives a delay and then an error. I tried another brand of external drive. This is also inaccessible. I can, however, access (read-write) all shared folders on the Mac's main hard disk.

I'm now copying over the drives content so I can see what happen when it's formatted as an HFS drive, but the transfer will take six hours to move between drives on the PC using USB 3.0, and then the same files will have to be sent from the PC to the the Mac over the network, which will take considerably longer.

By far the easiest solution would be to set up a Windows (or Linux) system as a server for the Mac. Sharing in that direction doesn't present any technical challenge, and Windows is more chivalrous than Mac in sharing its information with the enemy. In this case, however, I am using the Mac (Mini) as an entertainment server, and I want the media files to be local so I can take advantage of the Mac's quiet operation and impressively low power consumption.

Try this: make sure your SystemPreferences->Network->Advanced->WINS->Workgroup setting on your Mac is the same as your Windows workgroup. You may have to set up a new location (instead of Automatic) to accomplish that, but you need to do it so Windows can access the drive. Once they're the same, you can access the drive and read/write from/to it in Windows. I have an external 1.5TB connected via USB to my Mountain Lion Mac Mini and can use it from my Windows 7 Ultimate for everything except Windows Backup. Backup will see the drive on the network, but denies me access to it...even though I just copied files over and back to/from it on the Windows machine. Go figure. Someone figure out the Windows backup thing & we're in business!

BTW, the USB external drive is exFAT...

Thanks for the tip, Larry - I will try it with one of my other USB drives. For now, I've reformatted my Mac's external drive as HFS, and it was immediately accessible, with read-write access, on my Windows network. I tried moving files around, and moving and deleting folders on the Mac from a Windows machine, and everything works as it should. It's strange that the network configuration would have to be different with exFAT (assuming that's the problem). Re your Windows Backup issue, this sort of thing is usually caused by the backup program running under a different account from the account you use. I highly recommend Cobian Backup, which is free, has a professional set of features, and does a great job of scheduled backups. I like that Cobian stores files as files (rather than in an archive) which makes it much easier to get at your data in an emergency. If I've deleted a file by accident, I just go into the backup folder, rather than having to open a backup program. Cobian is usually pretty good at backing up files over a network, between different file systems.

...now mine's not working...(/facepalm)

OK, let's start over (/remove facepalm)...I now have my Mac Mini's USB external drive formatted as HFS by Mountain Lion. All 1.5TB in 1 partition. Windows 7 Ultimate has R/W access to the drive over the network (like duncanmkz). Windows Backup works (sort of), but only after I disable Comodo firewall. With C fw on, WB says the drive isn't available even tho Windows Explorer just R/W to it in a separate window (yes, I closed the WE window before Backup). Now, when WB starts, it chokes on the selection of the initial selection of the external drive on the Mac with "The specified network location cannot be used." After closing the dialog box and clicking OK on the Select Backup window (which now shows the previously-selected location as valid), click Next and Next and "Save Settings and run backup", and it starts! Backup progresses until about 93%, writing to the external drive on the Mac the whole time, then fails with error 0X8007054f. The external drive appears to have a complete backup on it, but it's not recognizable from the Windows machine for restore purposes. I've tried this 3 times with identical results. Anyone got any ideas on 1) why the Comodo firewall interferes the way it does, and 2) why Windows 7 Ultimate won't see a backup set it (apparently) created?

http://en.wikipedia.org/wiki/Comparison_of_file_systems