Thanks for the update. The driver loading process (with Security "protections") in Big Sur is so unreliable, it is crazy.

@midihead7

Open a System Profiler report (about this Mac).

Under the Software tab on the left, find and Click extensions
Now click on the "obtained from" column on the upper right.
Expand the upper window:
The middle bar pulls down, so you can view more extensions in the window and also have room below to see the information about each extension as you click on it. I would make it about half way.

Now, scroll all the way to the bottom, where you see "not signed" extensions in the "Obtained From" column. Every one of those must be deleted.

After you delete all the unsigned extensions and "unknown" extensions, you should delete the older identified developer extensions (anything dated before 2019).

I would remove:
HP printer extensions, everything more than a year or two old. (You can always reinstall newer printer drivers)If you still use Black Magic, see if you can get an upgrade, these are pretty old.

When you click on any extension in this window, the lower half window has details. You want the location, i.e, path to the file

The "location" is the path to the extension. You can select this path and "copy" it.

the remove command in terminal is this:
sudo rm -r
Then you need to make sure there is a space after r, then paste in the path

For example, if you were deleting an extension like an HP Printer, commonly an issue as it can date back to 2013, its "location" is this:
/Library/Extensions/hp_io_enabler_compound.kext

So the terminal command will be this:
sudo rm -r /Library/Extensions/hp_io_enabler_compound.kext

When all are deleted, then do this in terminal:

sudo kmutil clear-staging

followed by:

sudo kextcache -i /

I did the above and there was no change. I did however update to Mac OS version 11.6.1 yesterday and as soon as I did that, now the SoftRAID drivers are consistently loading properly without the need for the script or manually loading the drivers.

Open a System Profiler report (about this Mac).

Under the Software tab on the left, find and Click extensions
Now click on the "obtained from" column on the upper right.
Expand the upper window:
The middle bar pulls down, so you can view more extensions in the window and also have room below to see the information about each extension as you click on it. I would make it about half way.

Now, scroll all the way to the bottom, where you see "not signed" extensions in the "Obtained From" column. Every one of those must be deleted.

After you delete all the unsigned extensions and "unknown" extensions, you should delete the older identified developer extensions (anything dated before 2019).

I would remove:
HP printer extensions, everything more than a year or two old. (You can always reinstall newer printer drivers)If you still use Black Magic, see if you can get an upgrade, these are pretty old.

When you click on any extension in this window, the lower half window has details. You want the location, i.e, path to the file

The "location" is the path to the extension. You can select this path and "copy" it.

the remove command in terminal is this:
sudo rm -r
Then you need to make sure there is a space after r, then paste in the path

For example, if you were deleting an extension like an HP Printer, commonly an issue as it can date back to 2013, its "location" is this:
/Library/Extensions/hp_io_enabler_compound.kext

So the terminal command will be this:
sudo rm -r /Library/Extensions/hp_io_enabler_compound.kext

When all are deleted, then do this in terminal:

sudo kmutil clear-staging

followed by:

sudo kextcache -i /

I note you have not done a clean install since 2006 or earlier. Its time.

macOS is very different now, and not only do those apps and drivers not run, they can cause conflicts and issues, such as you are experiencing with the SoftRAID driver issue.

There are 50 apps alone that are ten years or older. You have some older apps from some dubious developers, that I would expect have security concerns.

Take the time this weekend, you will be much happier.

Start with a clean install, take care of the basics, then slowly move over other apps as you find they are needed. Plus, you are helping avoid yourself becoming a victim of expoits/hacks. Security should be higher on your priority list and starting over is a first step.

Maybe it is time for a clean install. You have more than 15 obsolete extensions from old macOS installations.

I could tell you how to remove them via terminal, but considering how old some are, I suggest you do a clean install, there are probably other bugaboos going on also.

Considering how we think this should be a near 100% fix, I am curious. Can you attach a support file? Maybe I can see a clue.