If you have saved your project with loop activated, close project/cubase. On open, the loop activated locators will still be where they were with loop purple and activated - but the playback cursor doesn’t loop - it just carries on.
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video proof
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Cant confirm. Works here.
Can you give more info. Where cursor is at, loop, tracks… Or just upload a simple cpr with the issue?
skip to 00:50 seconds
Windows 7
project originally created in 9.5
I tried several projects, from 8.5, 9.5 and I could not make it happend on windows 10.
I do have 3 controllers, 1 set to mmc and 2 to transport by generic midi. They all updated to project up on boot.
I also forgot about my Otari wich was loaded and synced to my transport, on first attempt here. Even that big old girl, was trying to loop 
I dont have win 7 on any boot here. So cant try it on same OS. Maby some one with win 7 can chime in and confirm the issue you are having.
Only way for me to miss a active loop is to use shuttlefw instead of transport start.