Hello... It should be installed already.  If you don't see it, then you can pull the installation package out of an installation zip file of the same version.  It's been there since 9.8.0, I think.  Look in the ~/Install/Modules/ folder.  

Hi - Thanks for the quick reply, Will! 
I do have the Resource Manager installed (on a test server currently). I was wondering whether there are newer versions of the Resource Manager that I could use in DNN 9.9.1. 
From what you're saying , it sounds as though the answer is no - the one version that shipped with DNN 9.9.1 is the newest version that will work - Is that correct? Thanks again
-Tom

Hi - Thanks for the quick reply, Will! 
I do have the Resource Manager installed (on a test server currently). I was wondering whether there are newer versions of the Resource Manager that I could use in DNN 9.9.1. 
From what you're saying , it sounds as though the answer is no - the one version that shipped with DNN 9.9.1 is the newest version that will work - Is that correct? Thanks again
-Tom

Yes, the minimum version in the Resource Manager manifest matches the DNN version it was released in, so a newer version would not install normally. I would highly recommend upgrading DNN instead. 9.9.1 has several known security issues, see https://dnncommunity.org/security

Upgrading from 9.9.1 to the latest version should be painless, just make sure to backup first.

Thanks Daniel. Yes, we're looking at our options for upgrading, but we're using Action Form. The newest version of DNN that works with Action Form is 9.11.2, also Action Form is only available as part of PlantAnApp now so it's become much more expensive. So we're looking at our optiions on that. In the meantime, I was looking at the Resource Manager on a test version running 9.9.1.

I wanted to ask - If we upgrade to DNN 9.11.2, will that version of the Resource Manager have a more list type view of the folders /assets (as opposed to the large folder icon panel in the 9.9.1 version?

Thanks

As Daniel mentioned, the modules that ship with DNN are tightly coupled with the version of DNN they are deployed with. It's unlikely in many cases that they can/should be used on other versions of DNN. Upgrading is always the best answer with these.

The more a site keeps up with upgrades, the easier and less expensive they are every time. This is because each upgrade pass keeps the technical debt (and time/effort) lower. Whereas, waiting and letting the upgrades stack up doesn't just add 1:1 upgrade time. It actually adds more like 1:3 or 1:4 the effort, depending on how tidy the rest of the DNN site administration is.

Thanks Will. Yes, we're aware of this and we do plan to upgrade DNN. At this point it looks like we can only upgrade to DNN 9.11.2 since we are using many Action Forms on our sites and they are not recommended for above DNN 9.11.2.
Also, when we do upgrade DNN , if we want to keep using our Action Forms we'll need to purchase a PlantAnApp license (which costs thousands) in order to get the Action Form license, so that we can keep our forms working.
So that's why we're taking a look at things and trying to figure out our best path.

Oh, that's a tough spot to be in.  Depending on how much you're using their tools, maybe you can find and use alternatives.  

My guess is that if they worked on 9.11.2, they will work just fine on 9.13.x, of course a backup or local copy should be done to make sure but there was no breaking changes in that version range, so that would be my plan A.