Can’t restore any backup

Hi,
I’m trying to restore a backup on a different site (migration). To perform the task I will follow three step:
1)Backup site with UpdraftPlus
2)Restore on new domain
3)Search&Replace in DB + wp-config tuning

Step 1) Is fine.
Step 2) Is impossible! I first had a problem with big files (Upload or Plugin folder 78Mb zipped, 251 unzipped) so I limited the backup size to 50MB. I had to repeat several times the restore, but at last it says “success”. But I have the same problem (impossible copy file) with a very small folder like Themes. My log is pasted at https://pastebin.com/d4eVMNRT, can you help me, please?

Thanks and regards

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