(FF 3.6.16) Edit Tools->Options, Applications to use 'rundll32.exe shimgvw.dll' for PNG in windows
The Tools->Options, Applications 'browse' tool will only let me choose one command with which to handle an extension, when it needs to be a more-complex command line with parameters.
e.g. for PNG files I want to add the Helper App command line:
"rundll32.exe c:\windows\system32\shimgvw.dll,ImageView_Fullscreen "%1""
(which is the Microsoft RAW Image Viewer, same as its current windows File Association). Because the only options I'm offered on this machine now when I click on a PNG file link are to Save it, download it with the FlashGot plugin, or Open with the Browse button. On other windows machines here, Microsoft RAW Image Viewer is the default Open with choice in Firefox 3.6.16.
I have already tried (with FF closed) moving the mimeTypes.rdf file from %userprofile%\Application Data\Mozilla\Firefox\Profiles\xxxxxxxx.default\ subdirectory, then restarting FF. The mimeTypes.rdf file was recreated, about half the size of the one I moved to a temp folder, but that did not restore the 'open' function to the windows default (i.e. when I double-click a PNG file in Windows Explorer, it opens in the Microsoft RAW Image Viewer... I got the desired command from the File Types tab in Windows Explorer's Tools->Folder Options).
The only options offered in the Action picklist are Always Ask, Save File, Quicktime Plugin 7.6.5 (installed/required by iTunes, which is also installed on the machine where Firefox opens PNGs in the Microsoft RAW Image Viewer just fine), and 'use other.' When I select 'use other' the Microsoft RAW Image Viewer is not in the list of Helper Apps, and using browse in that selector window does not allow me to enter the parameters for rundll32.exe to invoke the Microsoft RAW Image Viewer.
Thanks. p.s. It sure would be nice to have a 'Preview' button here to check formatting before clicking 'Post'.
User Agent Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.16) Gecko/20110319 Firefox/3.6.16 ( .NET CLR 3.5.30729; .NET4.0E)
Wšykne wótegrona (2)
The Windows Picture and Fax Viewer is a DLL and is started via a rundll32.exe call and can't be set as an application to handle images in Firefox 3 and later versions.
You need to set Windows Picture and Fax Viewer as the default viewer in Windows.
Then it should be listed automatically in the Mozilla Firefox Browse dialog.
From my original message: (i.e. when I double-click a PNG file in Windows Explorer, it opens in the Microsoft RAW Image Viewer... I got the desired command from the File Types tab in Windows Explorer's Tools->Folder Options).
So, apparently either english is not your first language, or you didn't bother reading my post and answered strictly by the Subject... Because the "Windows Picture and Fax Viewer" (as it was formerly called; now it's called the Microsoft RAW Image Viewer) is already the default viewer for PNG files in Windows. See attached image.
Thanks.