Problems after iTunes 12.8.3 update : Help!

Today I tried several things.

First to find a previous version of my iTunes files on Time Machine. Unfortunately the only ones which appear were the same as after the update.

Then I decided to try another solution (after closing iTunes) :

a/ Create a folder containing the three New libraries (iTunes, Genius and Extras). Put it on the desk.

b/ Create a folder containing the three previous same libraries dating from before the update (after recuperation of the two extras and genius libraries that had been put in the trash by iTunes after the update) and rename the "iTunes Library (damaged)" as "iTunes Library.itl". Put it on the desk too.

c/ Use Disk Utility SOS on all my MacMini partitions and disks (several times, in case…)

d/ Place a copy of the 2nd folder's files in the iTunes' folder.

e/ Take a deep breath and open iTunes…

I found again podcasts, genius lists and albums recently bought that had disappeared.

Don't know how long it will last but I keep my two folders (in case…)

Next step : launch Time Machine :-)

Hey Joseph and thank youfor your answer. But I have no connection problem with AppStore or iTunes. There is just a big mess in my local iTunes! I just discovered that Genius is also disactivated. The problem is more the disorder than the loss. And I don't see how to put again podcasts in their right place! (which is not the music section).

Thanks for your answer. I keep it in mind and if this "disastrophy" ;-) happens again I will follow your solution. Until now, mine is working. I just think that being on El Capitan (and my Mac mini won't support a newer OS), I will avoid any iTunes upgrading/updating now!

Thank you for your attention. :-)