Outlook 2010 crashes when replying to emails with digital signature

Outlook 2010 crashes when replying to emails with digital signature

I have Outlook 2010 with an Exchange account. Recently I upgraded to
Windows 8 and ever since, I have an issue where Outlook completely freezes
and crashes when I reply to specific emails. These emails are always ones
that contain someone else's digital signature. It should be noted that my
account also has a digital signature installed (which I already tried
reinstalling).
I have disabled add-ins and and tried running in safe mode but the same
thing happens. I also tried recreating the profile but it didn't help. The
one thing I found to fix the issue is to run Outlook as an administrator.
When I do so, replying to the problem emails works. Instead of freezing,
Outlook asks for my permission to use my digital signature. The problem
with this fix is that Outlook Instant Search is disabled when running as
administrator, so I can't use this fix.
Any ideas what I could do to resolve this, once and for all?