Scope won't start (MSO58)

Used to occasionally get a System Error upon boot, but as of this morning am totally unable to boot the scope.
Presently running firmware 1.38.1. I tried loading a USB drive with 1.40 and turning on power with tit inserted, but no avail.
Any tricks to try?

If this happen after the install of 1.38.1, then please install 1.24.9. If the scope was working after the installation of 1.38.1, then a repair may be needed.

To set up a repair RMA (model and serial number)
call 1-800-833-9200 opt 2. Or 1- 800-438-8165
Or send an email to rmarequest@tektronix.com
Or https://www.tek.com/en/service-quote
Or https://www.tek.com/en/services/repair/mytek_rma_request