https://pve.proxmox.com/wiki/Network_Configuration
If you made manual changes directly to the /etc/network/interfaces file, you can apply them by running ifreload -a
The document was saved successfully, but Excel cannot re-open it because of a sharing violation. Please close the document and try to open it again
Make a backup of the file
Open the file
Click on ‘File‘ and ‘Inspect Workbook‘
In my case it found ‘Custom XML Data’
If you don’t know where this comes from and what it does, remove it
Save it – should work normally now
https://answers.microsoft.com/en-us/msoffice/forum/all/the-document-was-saved-successfully-but-excel/edb4f192-546b-4fa9-8c04-42e3f631046b