What type of calendar - local or network?

Sorry. Was offline for a day. I'm not sure I understand the distinction, but here's a description. I'm on my own network, not part of, say, a business. The calendar is linked to and synchronized with my Google calendar and my iphone calendar as well as to a couple of subscription calendar services (holidays, a special interest or two). It does not reside in isolation on my PC. Trying to execute the Synchronize command does not accomplish anything.

I just checked out my address book. It's intact as well.

Is it possible that copying over the calendar is insufficient, that is, that some other piece from the old machine is in conflict with the new machine? When I installed TB, the new installation required creation of a profile, which profile I have now ignored. I also did not copy over two other profiles, including one which had "default" in its name.

I hope I haven't added too much more confusing data. Thanks again for your help.

Is it possible that copying over the calendar is insufficient, that is, that some other piece from the old machine is in conflict with the new machine?

Yes, that's exactly the case.

When I installed TB, the new installation required creation of a profile, which profile I have now ignored.

In your OP you stated:

I successfully copied my very large profile (a lot of mail) from my old computer to a new installation.

These are somewhat contradictory statements. On the new installation, did you start with a new profile, or did you copy over your existing profile from the old installation?

I also did not copy over two other profiles, including one which had "default" in its name.

Is it possible you did copy over the wrong profile which didn't have the calendar(s)?

If every thing is there in the new profile except the calendars I'd just recreate the calendars. They all seem to be network calendars, so nothing will be lost when deleting and re-creating them in Thunderbird.

Thanks. I have it set up so that it gives me a choice of profiles on start. It gives me all my profile names, including ones I did not copy over (I do not understand this), from among which to choose. I always choose the same one--the one I have been using for years, and the one which previously survived an identical copy and paste operation to the one I just used for the this new machine. That is the only one I copied over this time.

How does one delete and recreate calendars? I just went to new/calendars. I chose "network". It offered GMail calendars, so I chose that. There then appeared my complete list of calendars. The ones I use were grayed out and I could not delete or fully recheck these. The ones I no longer use were available to be checked and unchecked, but that's of no value to me. I wonder what could explain this behavior.

I guess I could go into the profile and delete or rename the calendar file?

Thanks again.

How does one delete and recreate calendars?

Open the calendar tab. In the left pane right click a calendar to be deleted - Unsubscribe Calendar Restart Thunderbird. Re-create the calendar after restart.

Thank you. Here's how that helped solve the problem. I was not displaying (I have never displayed) the left calendar pane. Once that was open I could follow the icons and figure out what to do--the calendars were there, just not displaying (eye icon, menu dot items). That also explains the "grayed out" phenomenon I previously noted when I went to New/Calendar. Next I'll add something to my google and phone calendars and see if they synchronize, which will then make the migration complete. I'm pretty confident about that. I'll let you know only if those entries fail. Thanks again.