External HDD ejecting itself

[phone5g]

I recently upgraded my 2012 MBP hdd to a ssd and bought an external enclosure for the old drive. I plugged it into my usb port and it was fine for about 30 minutes and then it began ejecting itself very frequently. Is this a common problem?

 

[highlystrange]

I have a similar problem: I have several external drives connected to my Mini. When the computer isn't used for a number of hours (overnight), each drive has a message about being ejected improperly. But when I dismiss the message, all is good. I was hoping the answer to your question might shed some light on my situation.

 

[Fishrrman]

I've seen that with some enclosures, myself.

Might be:
- problem with the enclosure (controller board? controller chip?)
- problem with the cable
- conflict between two or more enclosures/controllers (I realize you only have one)
- something else.

 

[ppenn]

I'm prone to believe it's an OS issue. this has been happening to me for 3 years and I just gave up because everyone makes the same suggestions and none of them are applicable.