Like John and you I usually do an image (Acronis) before OS updates, MAJOR SW updates, new HW installs (e.g., graphics cards), or updates to what I deem to be COMPLEX software (SW that takes forever to install and re-config and make play nice with all the other apps).

But Kontakt is a "no brainier" to uninstall, delete left over "crap," and re-install from scratch - takes maybe 15+ minutes? (save scripts and don't delete libs) so I don't run Acronis when I do Kontakt updates - but I run incrementals every night anyway.

Of course you need to have KEPT the actual older update executable file to get you back to 5.3, or 5.5, or 5.6 - whatever your safe version was. I keep ALL updates for all apps - "just in case".

If you didn't keep them I guess you are stuck with a image recovery if things do go awry for you.

Note no Kontakt update files (the actual executable that contains the update) are any longer available from NI site, so...

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For what it's worth: 5.7 installed without any issue and works without issue (so far on both Win 7 and Win 10) but we may not use it the same, have the same libs, scripts, configs, etc. My poor Win XP's machines are stuck back at 5.3. But then again I'm not an exclusive, or even heavy, Kontakt user. Also I know I am in the minority because I do not really like Kontakt anyway. Not becasue of its sounds - they are good, but becasue I do not like its interface and mechanics.

Good Luck
Larry

Win10Pro,i9,64GB,2TBSSD+20TBHDDs,1080TI,BIAB'24,Scarlett18i8,Montage7,Fusion 8HD,QS8,Integra7,XV5080,QSR,SC-8850,SPLAT,FL21&others,Komp.14,IK suite&others, just a guitar player-AXE FX III &FM9T, FishmanTP, MIDIGuitar2, GK2/3'sw/GI20