I have Seagate 2TB external hard drive. I am using this hard drive to backup my files (manually, not with Time machine). The main problem is that external hard drive doesn't work stable. The problem is that sometimes(very often nowadays) I cannot see this drive when I plug it to my Mac. Drive can be seen in disc utility but it can't be opened to copy files in it. I'm trying to verify and repair disc in disc utility but it also doesn't work. Do you have any suggestions guys to solve this problem?
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External HD Problems
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Yes I tried on both USB ports on my Mac. Actually the problem is only with this (Seagate 2TB) hard disk because I didn't have problems like this with any other device (1TB toshiba Hard disk, 500 GB WD hard disk ...).
I used to use this drive before I bought Mac too. It was in NTFS format. When I bought Mac I turned it to exFat. Now I still can read and write to disc without problem on windows based PCs. But as I said on Mac it sometimes doesn't open it on finder but shows on disc utility.
I used to use this drive before I bought Mac too. It was in NTFS format. When I bought Mac I turned it to exFat. Now I still can read and write to disc without problem on windows based PCs. But as I said on Mac it sometimes doesn't open it on finder but shows on disc utility.
Within Disk Utility you have the option to mount the drive (if its not being showing in Finder), did you try that? That may work, though it doesn't answer why its disconnecting in the first place.
Perhaps its a power fluctuation in the drive, and OSX is being more picky then windows.
Perhaps its a power fluctuation in the drive, and OSX is being more picky then windows.
I have seen this symptom caused by 1) bad USB cable, 2) enclosure controller on the way out, 3) Drive on its last leg, 4) bad enclosure connector/PCB card, and 5) drive drawing too much power from the computer (try one of those cables with two host connectors, one data + power, other power).
I haven't seen it, but I guess a worn/bad computer connector could also cause this symptom.
Probably not, but possible.
First try a different USB cable. If you have more than one USB port on your Mac, try a different one.
The exFAT format may be the issue. I dunno, maybe a search on exfat will turn up something. The only thing I recall is a few USB hubs and drive enclosures don't play well with exFAT. But that shouldn't be anything that just started.
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Some thoughts....
Does the Seagate drive have an external power supply?
Are you plugging that in when you connect it to the Mac?
If you are NOT plugging in the power supply along with the drive, the Mac may not be supplying enough "USB bus power" to get the drive going.
As someone else suggested, try a different USB connecting cable.
A bit of advice I offer elsewhere:
Too often I've seen posts (like yours) from people who use a "cross-formatted" drive on both a Mac and a PC, then suddenly start "losing their data" on the Mac side of things.
For a drive that is to be attached to the Mac, that you store important stuff on...
... it should be in -Macintosh format- only (HFS+, journaling enabled, GUID partition table).
If you need a cross-platform drive to share things between a Mac and a PC, use a "dedicated device" for that purpose, and ONLY for that purpose.
A USB flash drive works fine for such things.
But again, if it's IMPORTANT stuff on the Mac, keep it on a Mac-formatted drive.
My opinion only. Others will disagree....
Does the Seagate drive have an external power supply?
Are you plugging that in when you connect it to the Mac?
If you are NOT plugging in the power supply along with the drive, the Mac may not be supplying enough "USB bus power" to get the drive going.
As someone else suggested, try a different USB connecting cable.
A bit of advice I offer elsewhere:
Too often I've seen posts (like yours) from people who use a "cross-formatted" drive on both a Mac and a PC, then suddenly start "losing their data" on the Mac side of things.
For a drive that is to be attached to the Mac, that you store important stuff on...
... it should be in -Macintosh format- only (HFS+, journaling enabled, GUID partition table).
If you need a cross-platform drive to share things between a Mac and a PC, use a "dedicated device" for that purpose, and ONLY for that purpose.
A USB flash drive works fine for such things.
But again, if it's IMPORTANT stuff on the Mac, keep it on a Mac-formatted drive.
My opinion only. Others will disagree....
Yes my Seagate device has external power supply. I'm first plugging in and then connecting to Mac.
Actually I need to share things between Mac and PC.