New install Big Sur show two Volumes named ...Data & Update
Hi and Happy New year to all!. Installed Big Sur on a new formatted external 500GB SSD and initially all was fine, that is until I restarted from the new Big Sur external SSD to my iMac's internal HD (2007 27" iMac running OSX 10.13.6 High Sierra. Once restarted in High Sierra, I noticed two volume images from my external SSD with Big Sur, one named ..Data the other Update. I cannot use them as startup drives because they are not recognized in System Preferences > Startup Disk.
I formatted the new external SSD and installed Big Sur without issues. I decided to give Big Sur a test drive before committing it to my iMac's internal drive to determine compatibility with several Pro Video & Photo Editors.
Hopefully there's a simple fix for this.
Thanks for suggestions for a solution