Replaced SSD with external now Monterrey not opening disk images.

No errors, just every single Disk Image file I download, things like Google Chrome, Discord etc, not open. If I double click them nothing happens, I can mount manually using terminal, but not the external drives.

Also I plug in external drives and they don't show, they are shown in system report, all external drives are fully function and they work in lower versions of the OS and were working before the internal SSD failed. They are in a mixture of formats, none are read.

The bluetooth issue, no errors again, it's just off when I boot up, I turn it on and get a spinning circle on the bluetooth icon for around 10 minutes, but it is then usable. I thought this was a software issue, but I reinstalled multiple times in different ways and always the same issue. Running the same OS version as I was previously with the internal SSD.

@markshiel - Let’s check to see what the OS is programmed to open. Right click the file in question and jump to Open With what is it set to? You’ll need to do both OS’s to compare.

Thank you for helping me.

It's currently set to DiskImageMounter (default) which I believe is correct?

Edit: Just noticed something strange, I created a new admin user and now when I right click the disk image there is another option DiskImageMounter ( 480.60.1) which works, this is in addition to the DiskImageMounter (default), this doesn't appear in the standard admin account created during setup.

Edit 2: After further investigation this appears to be DiskImageMounter from the other older working OS installed on the second partition (I set this up so I could run some tests to figure out the issue while having an OS that I could use) this one is working. Very odd, still unable to use external drives though and although I tick always open application with, it doesn't seem to do this and I have to select manually every time, but this seems to perhaps point to where the issue is?

Edit 3: Found another Monterey install I had, the diskimagemounter for this doesn't work either, they are different versions, so seems to be an issue with diskimagemounter in Monterey and perhaps not liking that I have an external boot drive?

@markshiel - are you able to access the image within the bootable external as well as another external drive (second port connected)

@danj In Monterey no external drives will mount apart from the external boot drive.

If I change the Open with to point to DiskImageMounter to one from an older version of MacOS on a partition, I can mount Image files, but not external drives.

I used OpenCore legacy patcher to update to Ventura and Sonoma, neither of these have the issue, I'm convinced there is an issue with the Disimagemounter in Monterey when booting from an external SDD.

The only issue now is that Bluetooth is still taking around ten minutes to switch on after boot. This is another issue that only happens from Monterey onwards, but is not fixed by upgrading to Ventura or Sonoma.

It works fine after ten minutes though, looking in system report no bluetooth is listed, but it lists it under USB and detects it fine, in bluetooth settings it is listed as 'address: null', but then after ten minutes everything kicks in and works just fine. I'm unable to figure out a solution or seem to find any answers for this.