Firstly, may I ask why you are using such a dated version of the CMS? You will generally receive a better experience if you use the latest version, which is 11 at the time of writing.
The issue you are experiencing is occuring because you do not have a MediaDescriptor registered which supports .PNG files.
See the documentation in relation to this: https://world.episerver.com/documentation/Items/Developers-Guide/Episerver-CMS/75/Content/Assets-and-media/Media-types-and-templates/ - that's specifically tailored to CMS 7.5.
In a nutshell; you need to add the following class:
[ContentType(DisplayName = "Image", GUID = "{INSERT_GUID}")] [MediaDescriptor(ExtensionString = "jpg,jpeg,jpe,ico,gif,bmp,png,svg")] public class ImageFile : ImageData { }
Ensure you replace the INSERT_GUID text with an actual GUID.
I've just made a fresh install of EPiServer 7.5. But I can't upload files in the CMS. When I upload a file I get the status "Failed". When I hover on the status it says:
"There is no content type associated with the ".png" file extension."
No files work uploading. Anyone have a clue?