I got this error today opening an email in the Outlook Mail app on my Lumia 640XL running Windows 10. I am using the Insider app and am on the production ring:
There is not enough memory or disk space to update the display.
Currently the Outlook Mail app cannot be reinstalled on Windows 10 Mobile – this left me with the option of doing a hard reset as follows:
Swipe down from the top of the screen and then tap All Settings, System, and then About. Scroll down, then tap Reset your phone, and then follow the prompts.
Once I reset my phone and updated the Outlook Mail and Outlook Calendar app my phone functioned correctly again.
If you find an alternative work-around please let me know in the comments below.