Pegasus J4 - Catalina

  • Last Post 4 weeks ago
James Camelford posted this 09 April 2020

I have upgraded to Catalina 10.15.4

The kernel extension for the J4 driver is incompatible since it's 32-bit.

I've seen other Forum posts with a comment that they will update the driver to 64-bit.  Catalina has been out for months now ..... can you please advise the status of this.

This has bricked an otherwise perfectly usable RAID drive.


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Raghuraman Kannan posted this 14 April 2020

Hi James,

Pegasus J4 is one of our Legacy product. It has not been tested with latest MAC OS .

The last tested OS was MAC 10.12 . You can download the driver from below link.

Thanks !

James Camelford posted this 14 April 2020

Raghuraman, thanks for your reply.  However, it remains unsatisfactory.  While it may be a "legacy product" to you, it is a fully functioning piece of hardware to me; purchased new in 2014 - and  believe you continued to sell it well into 2015.  While on MOJAVE I was able to use it on 3 Macs - my MacBookAir (which I have now moved forward to Catalina-and it will not load), my 2013 MacPro and my 2017 MacBookPro (the latter two remain on MOJAVE). It's a great product and I appreciated its portability.

It's not a question of 'testing' it on Catalina - it's obvious that it won't work because the driver/kext is compiled in 32-bit and it must be in 64-bit to run. You've had that information for about 1-2 years.

It's up to you to make a commitment to upgrade/test and release a version that will run on Catalina, irrespective of whether you classify it as legacy - becuase it is a viable, useful product that is certainly within my usability span. Just because you arbitrarily deem it as legacy doesn't reduce its usefulness to me.

If you can't commit to that, well then I guess I move the other two Macs to Catalina and my Pegasus J4 will be 'bricked'.  And that means it will have to be replaced - and if that is the case, the probabability of me purchasing another Promise product is Zero.

I surely can't be the only person/organization in this position. So it strikes me you have an opportunity for excellence and good customer service here - one that can be farily easily addressed.  

Please step up to the plate on this one.


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  • Rich Freeda
Rich Freeda posted this 20 April 2020

I have the exact same problem.

Please be a responsible company and make a driver for the Pegasus J4 for Catalina. 

Otherwise this thing is a brick. I can't even access the data I have stored on it without finding another computer to transfer   This is irresponsible to your customers and the environment.

Please do the right thing!  

thank you,


Stefan Doering posted this 4 weeks ago

Dear Mr Raghuraman,

Dear Promise support,

I need also a driver for the famous J4 for Catalina, all my data is on it, the unit is filled with expensive ssd´s and is working perfectly fine!

It would render a big investment useless for me. (That would really be a reason to not coming back to your products and your company...).

It can´t be too difficult to provide an driver, it´s a great product, so you should not turn it into waste.

Yes please respect your loyal customers with supporting you products - in the end: it´s just a driver we need!!

Best regards: Stefan


James Camelford posted this 4 weeks ago

A few hours ago I received a notice that this forum had been updated with the post quoted below.  But it's from the eMail copy I receive and I do NOT see it within the that's confusing.


Here it is from the eMail

So, like Rich and Stefran - we are talking about the Pegasus J4 - which requires a 32-bit driver update for the product to work in Catalina.  If this note really is from the "Promise Team", can you please provide us with an official response regarding your plans to provide a driver for this unit that will work on Catalina.




Hi Stefan,

Kindly let us know the exact unit model to help you.

Also you can reach us through for quick response.


Promise Team

Stefan Doering posted this 4 weeks ago

So, like Rich and Stefran - we are talking about the Pegasus J4 - which requires a 32-bit driver update for the product to work in Catalina.  If this note really is from the "Promise Team", can you please provide us with an official response regarding your plans to provide a driver for this unit that will work on Catalina.




Hi Stefan,

Kindly let us know the exact unit model to help you.

Also you can reach us through for quick response.


Promise Team


Hi James.

so i went to and there i searched again. I found this link for an unsupported beta version ( for the Pegasus J4 from 2016 for MacOs 10.12. As far as i know, installing is on your own risk. I just installed it with my NewMacPro 2019 with Catalina newest update 10.15.5 J4 is up and running again, even with its usual speed (4 ssds - 800 MB/s with RAID). So finger crossed this is a working solution. Please report if it is working also for you.

All the best: Stefan from Germany

James Camelford posted this 4 weeks ago

Hi Stefan - thanks for posting that.  In fact, this is the version I had installed when I did my upgrade to Catalina on my MacAir and my MacBookPro - and the J4 did not work after the OS upgrade.  I have been using this version since it was released in 2016 (on all 3 computers) and that is what is left running now on my MacPro, which is still on Mojave.

But your post got me to thinking that maybe the software was simply un-installed or disabled during the upgrade by the OS and that was why it wasn't working.  Following your post, I did a re-install on the Catalina MacBookPro this afternoon (Sunday) which went fine and I re-booted and plugged the J4 back in and, low and behold, it was in the drive list.  

I opened a few folders - so far so good.  I located a folder of about 7GB of video recordings on my 20TB LaCie RAID and initiated a copy from the LaCie to the J4 to further check and see the transfer speed.  I got 1GB into the copy and my LaCie RAID went into recovery with disk 3 (of 5) down.  

The LaCie has gone into recovery mode now and it's re-building the array.  A process I expect will take into Monday. I've pulled the J4 from the MacBookPro Catalina system at this point.

So was this a co-incidence ????; or is there a possibility that the J4 kernel extension somehow conflicted with the other RAID.

I have no way of knowing at this point - so all I can do is let the re-build take place - and I won't monkey with it until it is clear and I have reviewed my backup status of the LaCie RAID.  I've also ordered a replacement 4TB IronWolf drive just in case disk 3 really was flaky.  I did replace 1 drive in this raid in mid-2017 so it's possible.

In the meantime I can re-install the driver on the MacAir and retry the J4 - safer since the MacAir doesn't have any other drives connected to it.

I'll report on these activities a little later in the weerk.

In the meantime, I'd appreciate any other feedback on your installation confirming it is still working fine and you haven't noticed any anomalies on your system.

Again, thanks for the tip.

regards, jc - Sunday 3pm, Toronto time.

Stefan Doering posted this 4 weeks ago

Hi James,

good news from my side: i copied tons of terrabites back and forth with the J4 all weekend - works well, so far not a single issue.

Well i am not really in the position of giving any qualified tips ( i am a musician ;-)...i am just trying (kind of desperatly) getting everything to work...(as you...;-)

But nevertheles: just a shot in the dark: BEFORE i installed this unsupported Beta-driver from 2016 wich we are talking about, i had found and installed (more by accident) an utility for the Pegasus J2 (or something) this one here:

from here:

I really don´t know IF there is any relation to that the old J4-driver now working ...?? (really just a guess!!). Anyway here it works fine for now and i just hope it will remain so!

Reading your´s hard to guess where is the culprit for the LaCie Raid issue, because there are a lot of other hardware involved in your case. I am just using the J4 with a blackmagic multidock with some normal ssd´s to copy things around...

Maybe just another hint for you: in my activity window, there is a now a constant deamon-process going on:

Process:         PromiseUtilityDaemon [580]

Path:            /Applications/Promise 

But again...i really don´t have a clou if that helps (and if that dameon is comming from the old 2016-driver or...the utility i accidently installed?) Anway - Really hope you find your way trough.

All the best Stefan


it's a pity that we have to experiment so helplessly around here and there is no real (good) support from Promise.

But maybe someone from the support team is reading this?



James Camelford posted this 4 weeks ago

And good news from my side (Tuesday, 6pm Toronto time).  First off, thanks Stefan for reporting that you did get that BETA driver to work.  I assumed it was not working after my rollover to Catalina and the drive wasn't recognized - but re-installing/re-booting did load the driver and I have tested it today on my MacBookPro and my spouse's MacAir.  Working fine on both (both systems are Catalina)- did about a TB of transfers including some bit-by-bit verifications afterwards.

The failure of my LaCie RAID-5 was entirely co-incidental and unfortunate.  I truly did lose Drive 3 because of a failure on the drive. It's SMART Status shows it's toast so it's in the trash tonight and I am currently re-building the RAID with a replacement HD.  Fingers crossed it will be finished overnight and I will have my redundancy back.

I'll look into the utility issues a little later in the week after I can get back to my laptop since it's tied up with the RAID re-build and I'd like to just leave it alone.

But thanks again for the tip.  Appreciated !

cheers, jc