Jeff,
That is great!  But we cannot find it anywhere.  We wrote our 
customization for ECT file attachments in 9.1, and we must have carried it 
forward to 10.0 and 10.1 unnecessarily.  In our Site, Org, and Library 
Preferences, I cannot find that particular preference using "Attachment" 
or "Change" or "File" as keywords.  My local PTC Global Services guy, who 
is really good, can't find it either.
Would you please tell us the preference name in Windchill 10.1 to allow 
ECT file attachments?  I bet it is right in front of my face, but I just 
can't seem to find it.
At the moment, our customization is not supported and has problems on 
certain browsers.  We even have to carry a warning, below, for our users 
to get help on the Create ECT page.  If you can give me a realy preference 
that works OOTB, then I can eliminate this buggy customization and get rid 
of all this unsupported stuff that clearly has problems, as you can see 
below.
The link "Read this..." goes to the following warning on our Windchill 
10.1 system:
ECT Attachment/Document Upload Preference Settings (INC000001858398)
This is an unsupported enhancement by PTC and was removed in 10.0 after 
the IE update on Windows 7 caused attachments to be dropped during ECN/ECT 
creation.  We are re-implementing the ability to add attachments to ECT?s. 
 However, certain combinations of client side software versions cause 
different behaviors and varying degrees of success.
The following preference setting combinations describe the resultant 
behavior. You will need to evaluate your requirements and change your 
client side settings to achieve the best results for your particular use 
case.
Software Version Combinations Tested:
Windows 7 - (Windows XP and IE 8 appear to be unaffected)
IE9 (32bit) - (32bit is actually faster than the 64bit version)
Google Chrome Browser: v24
Google Chrome Frame (GCF): v24