When upload images or files using PHP on IIS, the files are not accessible from website http due to 401.3 ACL permission problem.

 

Step 1

1. In IIS, click your Website. Under "IIS", double-click "Authentication".
2. Right-click "Anonymous Authentication", click "Enable".
3. Click your website again. Under "IIS", double-click "Authorization Rules".
4. If there isn't anything, click in the right panel "Actions"->"Add Allow Rule". Choose "All Users".

 

Step 2

Go to php.ini and set upload_tmp_dir to C:\Inetpub\temp\uploads

Go to C:\Inetpub\temp\uploads, change the permission of Creator/Owner to read / write / modify

Restart IIS and now the problem is solved.