Thank you for your detailed response. I hope the article was helpful. It looks like you've certainly followed the steps correctly. The "Uploads" folder should always exist within the root of your InstantForum or InstantKB installation. This folder has been present in all InstantForum & InstantKB downloads for several years and it should be present in your 2013 download.
We use this folder to store all user uploaded images embedded within forum posts.
To help I've included a image below which shows all the default folders which may help you compare. This is from InstantForum 2015....
It is possible to customize the default location uploads are stored so if this was customized during the original installation this may explain why you don't see an "Uploads" folder. You can set a relative path from your application root to the "Uploads" folder from within the InstantForum Admin CP > Forum Settings page or you can set a hard coded full physical path or UNC path to the "Uploads" folder within the InstantASP_UploadPath application setting within the web.config file for either InstantForum or InstantKB.
We don't check to ensure the folder you specify for uploads already exists. You will need to ensure the folder exists first and has the correct "write" & "modify" permissions for the windows account under which your application pool runs. Checking this folder already exists is a good idea and has already been added for the next update expected soon.
I hope this helps you troubleshoot further Parrish and understand the "Uploads" folder. If I can assist further with any additional questions of course please don't hesitate to respond,
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