cannot open or edit a file on external hard drive ntfs

NTFS is a very mac unfriendly format, it was developed for Windows and it had limitations on mac

NTFS is also not supported in any way by any version of OS X other than read only

NTFS formatted drives can not be backed up or used a time machine disks, they do not store mac permissions and the 3rd party tools used to write to them have been known to stop functioning with some OS updates

If you can not copy the files from the drive to the mac disconnect the drive cable, power it down and reboot the computer, then repower the drive and reconnect.

if this does not work you can back the drive up to a windows computer (have you tried another mac?)

then once you have the data reformat the drive a Mac Extended (Journeled) and use it on the mac without the NTFS limitations, however Mac Extended is not readable by Windows without 3rd party applications and Fat32 and EXFat formats also have limitations on Mac OS X, but writing to the drive is not one of them.

No, you don't need to but if you had one handy I'd say it's the quickest way to get full control of a NTFS formatted drive and not have to rely on 3rd party software.

whatever you are using to write NTFS on the Mac I'd suggest uninstall it, reboot, and see if you are able copy the contents of the drive and if so get the files off and format it. the NTFS drivers can be flakey. If the driver was working in Yosemite and broke in El Cap it's in the developers hands to fix it but I'd say it's point of failure to keep that drive NTFS on a mac.

your second option is connect the drive to your wife mac, share it over the network and copy the files to your mac from there. It will take hours (or longer) but you can then reformat the drive and drop the files back on it.

Like Jimmy said: writing to an NTFS drive in the mac requires third party software. The software you were using does not work in El Capitan.

I second Jimmy's suggestion to copy the contents somewhere else, then reformat the drive as OS X Extended (Journaled), and copy stuff back.

Or, if you need the drive to be also used with a Windows machine, format it as ExFAT (which is readable and writeable by both mac and pc).

James McKinstry wrote:

problem is that exfat does not like to write files that are over a certain size. and my tv does not see mac drives- so that is out.

i turned off/disabled any 3rd party file writing software

i put parallels on my mac- so now i can rename files and move them, but i still have to write with the mac. annoying but could be worse.

You are confusing ExFAT with FAT (also known as FAT32). FAT32 has a 4GB limit for file size. ExFAT, like OS X Extended, supports big files, no problem.

I cannot say if your TV sees ExFAT drives or not, though. That you'd have to look up on the TV manual, probably.

the single file size cap for file on an ExFat formatted device is 16GB

I'm guessing if Fat32 and NTFS can be read ExFat can too but I've stuck my MBP laptop into the TV with a VGA adapter and a stereo cable because the proprietary stuff habitually becomes a problem at some point and just run whatever I'm trying to watch through VNC full screen.

JimmyCMPIT wrote:

the single file size cap for file on an ExFat formatted device is 16GB

.

Not GB, theoretically it is 16 Exabytes, which is more than a gazillion... something like 16 Giga GB.

that's one **** of a typo I made.