on our site using an ssl we have Version 7.27.0.0 . on upload of a 128MB PDF we get an ERROR MESSAGE "object reference not set to an instance of an object" on upload of a 128MB pdf file.  Using latest version of GOOGLE Chrome and firefox as of 12/21/2018 - another error on the same file we are getting is  (chunk unexpectedly failed ).  I have oped a ticket regarding this, but no response yet (13E-23B0106F-0301)

what could cause this as we are seeing some unexpected results at different office locations.  some offices can upload fine, but others get 1/4 or 1/2 half of this file uploaded then it fails with errors above.

windows 2016 server

Database Version:    7.9.1
License Version:    7.9
Machine Name:    DA207
Operating System:    Microsoft Windows NT 10.0.14393.0 (64-bit)
Process Memory:    881 MB (64-bit)
ASP.NET Version:    4.7.3282.0
Current Identity:    IIS APPPOOL\MervacIncFiles