After letting CC Cleaner do it's thing on a Dell Precision 7760 Win 10, the mouse wheel scroll settings are affected. Scrolling in Outlook 2016 the scroll jumps 2-3 pages and not 3 lines as before. Mouse settings changes do not seem to be applied. Other programs, Excel, Chrome, etc.) seem to b operating normally.
As it's just affecting Outlook and not others then it wouldn't appear to be the mouse settings, but you may want to check them anyway.
Click on the Start button and type Mouse to bring up the settings controls.
Do a Restart (not shutdown) of the laptop to see if that solves the problem.
How many emails are in the folder?
With Outlook smooth scrolling may stop working if there are a lot of emails (more than 100?) and it will seem to jump instead.
Did you run the Driver Updater in CCleaner and maybe updated the mouse driver?
Try changing it to the generic mouse driver, see "Scrolling with the wheel" here:
https://www.msoutlook.info/question/441
A bit more unusual but another thing to check is your keyboard.
Pressing and holding a key can change how a mouse behaves, particularly keys like shift, ctrl, fn, cursor keys, etc.
If a key is 'sticking' then that could cause a mouse to behave oddly in certain apps.
Clean the keyboard, under the keys. As it's a laptop you probably can't pop the keys off so do as best you can with a cotton bud or similar, give under the keys a blow with compressed air if you can.