This looks like it's some kind of hosting environment issue, but did you try the suggested upgrade path instead of a direct upgrade?

https://dnndocs.com/conte...rade-path/index.html

Hello Timo
Thanks for your reply.
Yes - tried the suggested UG routes. All fail in the same way.
My environment is simply Win10 Pro - nothing special.
It might be interesting that the Docs install method which I used would not work with www.dnndev.me - I had to use localhost.
The only other varable is that I used Edge as the browser.
Now I am wondering if Ghostery may be the issue blocking something.

Also - when people talk about "unblocking"  DNN files what on earth do they mean?  

Unblocking: See here for example: What Causes the "File Downloaded from the Internet" Warning and How Can I Easily Remove It? (howtogeek.com)

Happy DNNing!
Michael

I'll assume from your question that you haven't been unblocking upgrade files before extracting them. Do it or you will have a failed upgrade or install, whichever you are doing.

Thank you Michael and Joe for your advice.
TBH: It is so long since I installed a localhost of dnn I had no idea that blocking was a thing.
Anyway - an unblocked install zip still fails on the module install section with a "Value cannot be null. Parameter name: type"
DNN8 installs fine any 9 series fails. See logs in install web page returns nothing.
Totally stuck on this.
Wah!

To add a liitle:
As the fail occurs with modules I am wondering if I remove all but base modules I might then install them manually in an effort to find the culprit?  Now 100% on how to do this.
 

Yes, if you are really trying to go from 8.0.4 to 9.8.0 in a single step, you really need to go an review the release notes for the intermediate versions. There are a number of breaking changes and places you need to be careful.

See https://dnndocs.com/conte...rade-path/index.html

And, as you read the release notes, you will find that modules need to be upgraded along the way.

I assume that your 8.0.4 is not a clean install.

Not trying to go to 9.8 all in one go.  Followed sequence you linked.
8.4 was a clean install.  No problem
Cannot install 9.8 clean - fails at 34% somewhere in modules.
Cannot UG 8.4 insantce either
All very strange.
.net at 4.7.2 

Given all of the other discussion, I'd guess that all of the issues are the same one.

So, assuming that you want to install DNN 9.8, let's go back to that.

1. Delete all of the files in your website directory.
2. Unblock the 9.8 install and copy the files into your website directory.
3. Browse to the website and the installer should start up clean.
4. Assuming this fails, take a look at the InstallerLogyymmddxxxx.resources file in Portals\_default\Logs. Are there errors, if so , what are they.

I assume (from the title of this thread() that this is a not for production installation. If so, can you try to do the install using nvQuickSite? That might provide some other clues.