NEVER had this problem before

[johnmcd]

I have a BRAND NEW iMac (2.3 GHz Dual-Core Intel Core i5 OSX 10.15.4.) I have several other Macs, all at my work (where I cannot go right now to test this.) The Mac in my home office seems to have the ODDEST bug.

If I attempt to send ANY file via messages (MP3, .png, whatever) from an EXTERNAL hard drive, the message fails, I have to relaunch Finder, restart messages, delete the conversation just to get it working again.

From the internal drive? No problem - zip - goes through.

Any thoughts? Am I nuts?

 

[hobowankenobi]

Could it be possible there are permissions issues with the external drive or some files/folders? How is the external drive formatted?

You could be nuts. But that is likely a separate issue.

 

[johnmcd]

Could it be possible there are permissions issues with the external drive or some files/folders? How is the external drive formatted?

You could be nuts. But that is likely a separate issue.

Thank you for calling a spade a spade. It really could just be a PEBKAC. I don't "think" so though. Been doing this for a minute.

Um, the drive? It's a 4 TB drive I've used on other machines. Formatted Mac OS Extended (Journaled), I write to it all day doing audio production. Read from it just fine.

Permissions? I've never touched it. (Me) Read & Write, staff Read & Write, everyone Read only.

 

[hobowankenobi]

OK. All sounds right. Good to rule out though.

Just for giggles, it would be interesting to see if any other external drive triggers the same issue. That would likley rule out the drive and files...but perhaps not the bus/port/calble...depending on how it is connected.

It could be a problem with Mail, not file location or drive. Let's see if anybody else has an idea.

 

[johnmcd]

Just for kicks, I plugged in a different hard drive, and dropped some files on it. Attempted to send those files. Same result. (It's only with Messages that it fails.)

 

[satcomer]

I believe it might have to do if you are on an I processor and T2 chip!

You have to shutdown every app running, boot into Recovery Mode!

So just follow the steps to turn of max protection:

 

[hobowankenobi]

Just for kicks, I plugged in a different hard drive, and dropped some files on it. Attempted to send those files. Same result. (It's only with Messages that it fails.)

OK, that likely proves nothing to do with the drive or file permissions. Outside chance it could be the bus (assuming USB). but that seems doubtful.

I would try testing with T2 security off as Satcomer suggested. Even it if does not solve the issue, it would rule it out.

 

[johnmcd]

Nada. No T2 chip over here.

 

[satcomer]

Nada. No T2 chip over here.

Then sense you have an older Mac Try a Reset NVRAM or PRAM on Your Mac and let it bong twice before letting it boot normal! This usually reset the Controller Chip for ports in your Mac!

 

[johnmcd]

Then sense you have an older Mac Try a Reset NVRAM or PRAM on Your Mac and let it bong twice before letting it boot normal! This usually reset the Controller Chip for ports in your Mac!

I can certainly try that, but it's not an older Mac. It's brand new. I've only had it for six weeks or so.

 

[satcomer]

I can certainly try that, but it's not an older Mac. It's brand new. I've only had it for six weeks or so.

Why didn’t you say this before?

Sense it’s new it will have a T2 chip inside it! Follow the steps to turn down or off the T2 chip secure oane in menu item Window I think.

 

[hobowankenobi]

Why didn’t you say this before?

Sense it’s new it will have a T2 chip inside it! Follow the steps to turn down or off the T2 chip secure oane in menu item Window I think.

Actually...the newest iMacs (as of now) still do not have the T2. Kinda strange, but true. I expect the next refresh to have them, but probably takes a full redesign of EFI, SMC, Logic Board, maybe more.

I actually expected the last refresh to add T2....but (I assume) is was just a minor CPU/component update, and they did not have the time or need to do a full refresh.

OP: I am out of ideas. I would suspect it is a software bug, either OS or Mail. You could always try an OS reinstall, though that seems a bit drastic.