External Hard Drive incredibly slow after High Sierra

I really do not think it is the HDD failing. It's not even a year old, and I do not have any other HDD to try anything else.

In reply to HDD's fail after a lot of activity, how has there been major activity on it? The computer upgraded, not the HDD.

Thats a joy, Time Capsule filled up yesterday, for some reason unknown to me I decided to wipe it and order a new HDD which comes Friday. Thats whats concerning me now as I do not have a backup so if something goes wrong im done for.

What is the best course of action? Hopefully Apple will have a fix for this?

I've just tried copying a file from the HDD to the iMac, it was very fast this time. Also, moving it back on was also fast. It's still incredibly slow to load folder contents I haven't opened yet though, and im sure once I restart the HDD it will have to catch up all over again. Nightmare.

Just tried opening another folder, I got the spinning wheel and it froze, had to force quit Finder as it said "not responding"

This is really getting on my nerves, and I'm worrying that leaving the HDD on + connected was a bad idea when updating, but surely this shouldn't of affected it?

How many times do I have to say this is not my HDD's problem, but obviously software? Why would my HDD suddenly start failing directly after the High Sierra update? Either a coincidence or an obvious software issue, as things aren't loading properly and causing a huge amount of load on my CPU. If the HDD was failing it just wouldn't be working or even booting, and would be clicking every few seconds, it's not clicking - it's noisy as if it's under load which is normal! Don't tell me thats a HDD failing either as my other 2011 iMac is very noisy and has been since new.

As for stop posting on the internet, good idea. This is getting me nowhere, thanks for everyones input.

I got my iMac upgraded around 2 years ago to an SSD as I had a 5,400rpm HDD which was hellish slow. The SSD is a Kingston 250GB SSD, and hasn't missed a beat. I very much hope this isn't the cause to my issues, I would doubt. I'm still pointing the finger to software, but theres nothing I can do I guess but hope Apple get reports for the same issues and hopefully a therefore fix, or maybe my HDD is still indexing? How long should indexing take? Theres around 1.81TB of stuff on the HDD.

A quick update: I've noticed the HDD seems to be speeding up a little now, things aren't taking half as long but still are taking longer than they should, is it perhaps an indexing issue?

I don't think so, iconserviceagent seems to flare up when trying to load the folders contents, once they are loaded it's fine and the computer runs perfectly.

I've got to say, the HDD is slowly getting faster, it's still however very slow, i've had the HDD/iMac constantly on for around 5 hours, but it seems to be getting faster now?

Nah scratch that, i've had to put it back as it was fine until I went into some folders and all custom icons/layout had gone, and was not coming back. I thought I fixed it then -_-. I guess I'll have to wait for the bug update in around a month and see if that improved my performance. Totally disappointed with this software, absolute rubbish

Okay right, unless you have anything to help me with then don't post as you're pretty annoying. I have an issue as do others that CLEARLY is software and not HDD failure, you're telling me other peoples posts with the exact same issues directly after this "update" is hard drive failure? You're wrong.

You've literally spent this whole time giving useless info and not advising to clear caches or certain files that could improve, you're just saying my SSD is duff, my HDD is failing, I have 3rd party cleaning software and thats the cause of all my issues including the few others that have commented. Ok - shall I throw my mac out the window then? Might as well.

Please stop.

Thank you, finally someone with a brain. We'll have to wait for a bug fix then, and i'll learn by not upgrading my mac to the next software next year!!! What a total mess.

Again, before I get any comments back to what i said: Why would a failing HDD suddenly come out when the software is installed, with mulitple people - why would it slow the computer down when trying to load folder contents, but as soon as the folder contents are loaded or the drive is no longer connected, the computer works fine. Highest CPU load is from iconserviceagent.

In reply to the high load sounds from the HDD, it's been silent, i've been watching the Activity Monitor and as soon as iconserviceagent popped up (no idea why either) it made sounds. I know what a failing HDD sounds like, and indeed a dead one. This HDD has always made sounds under high load since new, it's 9 months old. My 2012 iMac which is now my dads with a HDD has always made loud noises since NEW - so if thats failing it's done alright for 5 years. Cmon seriously, you're barking up the wrong tree if you think it's mechanical.

Pichini13 if you have any work around or improvements please let me know. Do you have any videos on your HDD, before they open does it show a window with "verifying"? I'm not sure if this points to a security feature going loopy. Either way it's something new with OS High Sierra thats messed this up.

I wish I could go back to Sierra, but my Time Capsule got full, so I removed my HDD from the backups and backed up the system, only to today upgrade it to APFS which doesn't support Time Capsule (thanks for the warning Apple) so i'm now left with no Sierra backup, only this garbage. So i'm stuck.

How do I file a bug report with Apple? I'm definitely going to do it as I cannot stand for this.