Nodes wont render / substance locking up

[lllllHOSSlllll]

Hello everyone,

I have been using Substance Designer for a while with no issue, as well as being able to import substance files into the Unreal Engine using the plugin with no issue.  Yesterday when I tried to import a substance file into the engine the maps would import as white texture maps.  Then when I re loaded substance designer,  it wasn't rendering my nodes for the thumbnail preview and getting stuck trying to render them.  I then would have to force close substance because it would continue to run in the background.  So I tried contacting our IT team to disable their firewall and antivirus and then ran the software to no avail.  I uninstalled substance and reinstalled and still the same issue.  Again Substance has been working perfectly for me and I have been importing my sbsar files into Unreal just fine. (Even a few minutes before this issue)  I attached my log file and a screenshot as well.  Thanks for your help everyone!

[lllllHOSSlllll]

Update:  I uninstalled Substance and downloaded a previous version and still having the same issue.  Kind of stumped here.

[lllllHOSSlllll]

Update:  I think its something inside of the file I'm trying to work on.  After reinstalling substance and trying to recreate the problem,  I notice that I can open some of my other files just fine.  Then when I try to open this specific file it gets hung up.  Then i wont be able to view any nodes anymore from any of my files.  It wont even preview a uniform color node.  I created this file in the spring version and ended up having this issue start in the spring version as well.  I don't know what it is but I'm trying to rebuild the material now to see if I can find the node that's causing this mess.  Would it help if i attached a substance file?

[lllllHOSSlllll]

Update:  I rebuilt the file and can only come to the conclusion that i had a node or combination of nodes in my graph that caused the issue.  (Possibly from not optimizing my graph)  I rebuilt the file the same way and used all the same nodes. (That I could remember)  I cleaned up the frames and such but I'm still stumped as to what caused it.  My problem seems to be fixed but beware the rouge nodes i guess.