Try this: highlight inbox, rightclick, select properties and then select repair.

Merci de votre suggestion. malheureusement le problème n'est pas résolu. auriez vous une autre solution ? Merci

Is this an IMAP account? If so, my first suggestion would be to exit Thunderbird and, with windows file explorer, locate the profile and delete the inbox, inbox.msf entries for the account. If unfamilar with profile folder, - click help>troubleshootinginformation - scroll down to 'profile folder' and click 'open folder' - exit thunderbird - you are now in profile. click the imapmail folder, then the 'account' folder and the inbox and inbox.msf should be visible. delete them. - on restarting thunderbird, the folder will be recreated. And I HOPE that resolves the issue. I am not experience well in troubleshooting mode, so the problem may need guidance from someone else if my suggestion does not work.

Sorry,

is not  a IMAP account, it is a POP ?

Je ne vais pas me risquer à faire votre solution.

Merci have a good day

True, that would not work for POP. However, part of that approach is safe. You could delete the msf file, as that is the index. the account would be in the Mail folder, possibly Mail\<POPaccountname>\inbox, inbox.msf.

An alternate approach would be to - install the importexporttools NG addon - highlight the inbox, rightclick and select the importexport option to export eml format. That may retrieve the messages individually as eml files that could then be imported back to Local Folders with the same addon.

Bonjour David

D'abord merci de vos réponses, mais les solutions proposées étaient un peu trop technique pour moi......

Mais je dois vous informer qu'au bout de plus d'un mois de problèmes tout est revenu normal (comme par miracle !!!!!)

Encore merci HAPPY NEW YEAR

A true Christmas miracle. :) I am pleased that all is well. And all the best to you for 2025.