REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\InternetSettings\Accepted Documents]
"4"="image/png"

[HKEY_CLASSES_ROOT\.png]
"Content Type"="image/png"

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\image/png]
"CLSID"="{25336920-03F9-11CF-8FD0-00AA00686F13}"
"Extension"=".png"

[HKEY_CLASSES_ROOT\MIME\Database\Content Type\image/x-png]
"CLSID"="{25336920-03F9-11CF-8FD0-00AA00686F13}"
"Extension"=".png"