Miss_B

Based on that error, since it's trying to insert a post using a 0 ID, I guess AUTO_INCREMENT for the ibf_forums_posts table isn't properly set. 🤨

The compatibility checker would not check to see that it could access your MyBB installation. That is what is happening now in the conversion and it is stating that it cannot do so via the given path provided or the path provided is incorrect. If you are unsure how to ensure that permissions, ownership, and paths are correct, you may wish to contact a server administrator for assistance or simply, a second look (as we've all had those moments 🙂 ).
This may be obvious but some aren't quite aware so I will say it just in case. Keep in mind that your Invision Community instance and MyBB instance need to be on the same server to do this conversion.

Well that last bit... that's it hahaha It's working now, we moved the files over from the old server to the new one and it's going. I was about the post a reply we found the issue. 
 

You would need to contact your hosting provider to inspect the restore that was done. I'm afraid, this is not a software issue but rather a database issue. If a partial restore was done, this is what is causing your issues and would need to be a full restore.

It took most of the day and a ton of trial and error fixes.
First main issue was I could not download the software from the client area.
After I made this post I was able to.  I reuploaded everything except the Uploads folder
Did many other things mainly with htaccess and SSL.
What I did absolutely think worked best was changing in the conf_global area 'installed=true' then did a site update.
A cumulation of all those things and so far so good.

While I appreciate what you are saying there, the tool cannot access that location unfortunately, and has been used on many many occasions. Have you also checked you are converting from a version in which our converters are compatible with?  
 

In this screenshot it asks for the path to the MyBB forum, whereas you have entered the one to the avatars.
I haven't used MyBB for quite a while, but I do seem to remember vaguely that the paths were defined at the MyBB settings page. You can copy it from there.

Would ensure that your theme is compatible with the latest release and also disable any third party applications/plugins.

We've released some news on Invision Community Five, but third party developers won't have enough information to get started on updating their apps. We're at the peak of the mountain now and ready to start showing more in the coming weeks.
I am really excited to start showing off the culmination of just under six month's work from our team.

@andavis, this looks to be a php incompatibility issue by looking at the error message. To add to the above, what was the latest change made either to the forum or the server prior to this error happning?

@andavis, this looks to be a php incompatibility issue by looking at the error message. To add to the above, what was the latest change made either to the forum or the server prior to this error happning?

This function was DEPRECATED in PHP 5.3.0, and REMOVED as of PHP 7.0.0.
Which version of IPS are you using? To use recovery mode, you are probably running version 4.x.x
Which PHP version are you using - check in your server, it should be above 7.x.x and even above 8.0.0
What does your host support say about this condition of yours?
 

I would guess in the next couple weeks. It's almost to the point we can show people things.

Find a better host. 

Cool, @Adriano Faria! I didn't know that. All got, I've PM'ed her.

Gabriel, the app to redeem the keys was developed by me and it's available for those who want to use it. You won't find it on all contributors boards. A few are using it and they seem to be happy with it ( @DawPi @Nathan Explosion @onlyME ).

You can pm me the key at my forum. 

Third party apps/plugins/themes were never supported by Ipb. i.e. Ipb never provided support for issues caused by third party stuff. 

Great, it works! Thanks!

Add the code posted by Daniel above, save the changes and try to uninstall that app again. 

Post in the application's support topic for help:
 

Pretty obvious:
 

Thank you for being a client! The Invision Community Marketplace is closing October 30 2023, so I am moving all of my files over to my personal site https://www.yourforumservices.com. 
How to transfer Marketplace files from IPS to me -- read this link Need help? Browse my new support topics hosted on https://www.yourforumservices.com Want to buy? Browse my updated files hosted on https://www.yourforumservices.com Bookmark https://www.yourforumservices.com and the new Marketplace Directory https://www.invisioneer.org/.  

Hello all, I just wanted to report back that I have swapped hosting services and now have php 8, and while I am still waiting for DNS to propagate I have been able to update to 4.7.13 and everything seems to be fixed! I appreciate all the help, thank you again for the support!

@Miss_B can't find where to insert the keys in your forums! 😞 It seems the key system isn't activated at https://www.yourforumservices.com/index.php?/keys/