Internet Explorer knowing MIME types list

lol. when i develop upload function in my site, mostly tested on Mozilla & Chrome was alright but when comes to IE, my system catch error when uploading the image. i dump all attribute and found the MIME type is not like usually type. It was pjpeg, P stands for Progressive. the problem because i not includes filter image/pjpeg & image/x-png. after i add it, all fine :)

*act, it was my 1st time develop upload function. so noob =.='

So this is what i've found googling for IE

Known MIME Types IE 

MIME Type	Description
text/plain	Plain text. Default if data is primarily text and no other type detected.
text/html	HTML. Default if common tags detected and server does not supply image/* type.
text/xml	XML data. Default if data specifies <?xml with an unrecognized DTD.
text/richtext	Rich Text Format (RTF).
text/scriptlet	Windows script component.
audio/x-aiff	Audio Interchange File, Macintosh.
audio/basic	Audio file, UNIX.
audio/mid	Windows Internet Explorer 7 and later. MIDI sequence.
audio/wav	Pulse Code Modulation (PCM) Wave audio, Windows.
image/gif	Graphics Interchange Format (GIF).
image/jpeg	JPEG image.
image/pjpeg	Default type for JPEG images.
image/png	Internet Explorer 7 and later. Portable Network Graphics (PNG).
image/x-png	Internet Explorer 7 and later. Default type for PNG images.
image/tiff	Tagged Image File Format (TIFF) image.
image/bmp	Bitmap (BMP) image.
image/x-xbitmap	Removed from Windows Internet Explorer 8.
image/x-jg	AOL Johnson-Grace compressed file.
image/x-emf	Enhanced Metafile (EMF).
image/x-wmf	Windows Metafile Format (WMF).
video/avi	Audio-Video Interleaved (AVI) file.
video/mpeg	MPEG stream file.
application/octet-stream	Binary file. Default if data is primarily binary.
application/postscript	PostScript (.ai, .eps, or .ps) file.
application/base64	Base64-encoded bytes.
application/macbinhex40	BinHex for Macintosh.
application/pdf	Portable Document Format (PDF).
application/xml	XML data. Must be server-supplied. See also "text/xml" type.
application/atom+xml	Internet Explorer 7 and later. Atom Syndication Format feed.
application/rss+xml	Internet Explorer 7 and later. Really Simple Syndication (RSS) feed.
application/x-compressed	UNIX tar file, Gzipped.
application/x-zip-compressed	Compressed archive file.
application/x-gzip-compressed	Gzip compressed archive file.
application/java	Java applet.
application/x-msdownload	Executable (.exe or .dll) file.

new found MIME type :
image/x-citrix-png
image/x-citrix-jpeg
image/x-citrix-pjpeg

is this related to this? Citrix Systems

Some are not registered with IANA

Source : msdn