Same problem - copy from one material BP (no problems) - paste into another - fine (several nodes at once). Copied single (Lerp) node from material, no problem, paste to second, PROBLEM. Memory warnings as system memory was almost instantly swallowed by Editor - then BSOD (SYSTEM_SERVIE)EXCEPTION (Win32k.sys)) which I have never got before. System isn’t new by a fair shot, but everything else works fine in UE4 even with VS2013 and other stuff open, so this really is a problem with the paste functionality in the material editor. ATI Catalyst version 13.1 (although driver is from 13.4 - not possible to upgrade further - HD4650 2GB) - DXDiag attached FYI:
Edit: BTW forgot to mention UE 4.5.
Edit 2: Just to say - no problems copy/past in othe BP’s - Level, Anim, Mesh/Actor, Class, whatever - only Material. A single unconnected node pasted into the MatEd should not cause a large memory spike nor a crash of any sort as it will not affect the shader anyway (being unconnected), there is a bug in the MatEd wrt pasting.
PS: Converted to comment
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