I'd pretty much wager that a JPEG on your system shows the DDE setting for what you asking, but if not:
Note: Either one of the following may be used and either one may also include at the end starting with a space -nohome %1 or -nohome. Please note the instruction in [Q256953].
''C:\PROGRAM FILES\INTERNET EXPLORER\iexplore.exe'' or ''C:\Progra~1\Intern~1\iexplore.exe''
Check the Use DDE box and then input the following for boxes 1, 2, and 4:
''file://%1'',,-1,,,,,
iexplore
WWW_OpenURL or WWW_OpenURLNewWindow
I would like to open images (eg jpg, jpeg, etc) in IE 6 so they open in the same IE window in full screen mode. I recall that I can perform this task under folder options, assigning the extension to IE, and entering the codes under Use DDE, but I do not recall what I must enter under Use DDE. Can anyone help?

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