In the past, Internet Explorer supported OLE so it could render a webpage, generate an image of it and pass that on to other applications, like ThumbsPlus. However, it could also be used to render malicious code, and so Microsoft disabled this functionality.
You can re-enable this functionality
on your own risk by editing your registry. A ready-made .reg file that does this (when you double-click it after saving it) can be downloaded from line item #162, "Restore HTML, HTM, URL Thumb View", from [link=http://www.kellys-korner-xp.com/xp_tweaks.htm]http://www.kellys-korner-xp.com/xp_tweaks.htm[/link].
That particular .reg file also enables thumbnails for a few other formats that you may not be interested in though. The lines to keep for .htm, .html and .mht functionality are these:
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\SystemFileAssociations\.html\shellex\{BB2E617C [etc.]
@="{EAB841A0-9550-11cf-8C16-00805F1408F3}"
[HKEY_CLASSES_ROOT\SystemFileAssociations\.htm\shellex\{BB2E617C [etc.]
@="{EAB841A0-9550-11cf-8C16-00805F1408F3}"
[HKEY_CLASSES_ROOT\.mht\ShellEx]
[HKEY_CLASSES_ROOT\.mht\ShellEx\{BB2E617C-0920-11d1-9A0B-00C04FC2D6C1}]
@="{c5a40261-cd64-4ccf-84cb-c394da41d590}" note that some of the the original lines were too long to copy here, so I edited them with '[etc.]'.
Do not use these (now crippled) lines - use the .reg file linked above.In ThumbsPlus, your file type definitions (
Options | Preferences | File Types, look for .HTM in the Documents category) should be as follows:
For .HTM:
For .HTML:
For .MHT:
When you've done this, reboot and see if it works. If it does not, you may have to change the "Load Using" value for .HTM files from Internal to OLE.
I hope this helps!