Illustrator last update and arrow keys

Yes is much better for you when posting on the forums to state your operating system and list any and all plug ins or nonstandard software that affects your OS or Illustrator.

More Thorough Reset Your Preferences

Quit Illustrator

Finder >> Shift Command G

~/Library/Preferences/Adobe Illustrator 21 Settings/en_US*/Adobe Illustrator Prefs

rename Adobe Illustrator 21 to Adobe Illustrator 21 old

Reset Your Other Preferences

Quit Illustrator

Finder >> Shift Command G

~/Library/Application Support/Adobe/Adobe Illustrator 21/

rename Adobe Illustrator 21 to Adobe Illustrator 21 old

Press Win+R -> appdata -> Roaming -> Adobe -> rename folder Adobe Illustrator 20 (or 21) Settings to any other name.

Hi Arzallus,

Sorry to hear that you are facing issues with Illustrator while trying to move objects. This could happen due to a couple of reasons like corrupted preferences, corrupted file or a conflicting app like an anti-virus.
I would suggest you to check with a new document first. If this happens with all the files, including new one, you should check for a conflicting app, as informed above. If you have any, disable it and then check. The last thing you should try is to reset the preferences as suggested by Ton. For that, see: adobe.ly/1z4XLJH
If none of the above suggestions work, please share your system details, OS version, exact AI version and any third party plugins installed.

Regards,

Om

Try to reset the Preferences:

How to set preferences in Illustrator