Does the issue occur in a new sandbox with default settings? (with and without the Acrobat template, as suggested above) ?
Do the pdf files open in IE outside Sandboxie?
I have re-tested using Windows 10 x64 CU//Win 7 x64 + this link https://cdn.vizio.com/documents/e32d1/um-e32d1.pdf + Internet Explorer and did not encounter any issues.
See if your Antivirus software has any specific features that modify Internet Explorer.
It should be a direct link to a specific set of steps provided by Syrinx, followed by a user's setup of Kaspersky + SBIE, try this:As for the other link, it's a search of the forum bringing up 29 results for Kaspersky ...
viewtopic.php?f=11&t=21539&p=129509&hil ... ky#p129509
According to the second user IE just won't work with Kaspersky. So I am wondering if this is just pdfs or anything else you try to do via IE.
Regards,
Barb.-