I am trying to post an SVG file I made in inkscape on a forum for feedback and it says file not acceptable. I tried reading the FAQ's but didn't find the solution. How do people get their images on here to share? Thanks in advance.

If you need to share an SVG in order to get help with what you're doing, you should post it in the Help with Inkscape forum. SVG uploads are disabled in the Show It Off forums, because the admin feels that finished or nearly finished work is better uploaded to a dedicated host (ImageShack, MediaFire, DeviantArt etc.). The ability to upload attachments on this website/forum is an option, and may not always be available (over the life of the website/forums). (So if someone uploads a finished work, and later the option is disabled, their image will no longer be visible.)

So you could upload the SVG in the Help forum (if you need help), and/or upload the PNG, JPG, or whatever, in Finished Work or WIP forums (if you want comments on your work).