Viewing PDF in IE11 w/ Acrobat Reader

Windows 7 Pro 32bit, Inteset Secure Lockdown v2: IE edition build 2.00.131, IE 11 with current updates.  Acrobat Reader DC.

We have a few locked down machines that are used to access an internal web portal.  Haven't had issues logging in or using the portal besides this.  Currently trying to get them to view and eventually print PDF reports.  Been trying with progressively looser restrictions, but every time the result is the same: clicking the "generate report" button produces no change except an error popup saying "This operation has been cancelled due to restrictions in effect on this computer."

Using the same procedure on the same machine while Inteset is disabled works: clicking the button opens a second tab containing the report displayed with Reader.

They do not use kiosk mode or private browsing, and I've progressively unchecked settings up to the set below.

Allowed:

System:
Local drives
Desktop
App install

IE Lockdown:
All General options except new window
Favorites
Tabs

I've also tried adding AcroRd32.exe as a background app, but unsurprisingly that didn't fix the problem, just made the standalone Reader open on startup and get in the way.

I've confirmed with the web app devs that the server response to the HTTP request has a header like this:

HTTP/1.1 200 OK
Cache-Control: private
Content-Type: application/pdf
Server: Microsoft-IIS/8.0
X-AspNetMvc-Version: 5.2
content-disposition: inline; filename=powerTrackReport.pdf
X-AspNet-Version: 4.0.30319
X-SourceFiles: =?UTF-8?B?QzpcVXNlcnNcSmFyZWQuQmxhY2tcU291cmNlXFdvcmtzcGFjZXNcUG93ZXJUcmFja1xQb3dlcnRyYWNrX1dlYlBvcnRhbFxQb3dlclRyYWNrX1dlYlBvcnRhbFxScHRcU2hvd1JlcG9ydA==?=
X-Powered-By: ASP.NET
Date: Fri, 05 Feb 2016 15:34:06 GMT
Content-Length: 33216

and the entire content is the PDF.

It may be because the "Internet Explorer Lockdown > General > No Downloads" option is enabled. IE downloads the PDF before it opens it.

That was the first setting I unchecked and tested.  To clarify, when I say "Allowed: [...] All General options except new window," I mean that all options under Internet Explorer Lockdown > General were unchecked, except "No new window" which was checked/enabled.  So all the options I listed in my first post are restrictions I've lifted.  Hope that helps.

IE opens PDFs in a new tab (which is considered a new window) if the webpage link is defined to do so, in that case the "No New Windows" option must be disabled (unchecked).

Sorry for not replying sooner.  Disabling "No New Window" fixed the problem!  Thanks for the help.