Hi @Volker Blockhaus ,
Please kindly understand that currently in Microsoft Q&A we only support English and I am trying to read your issue via machine translation now, if I have any misunderstanding, please try to re-edit your question into English so that we could better help solve your issue.
If I have retrieved mails via pop3 and delete them or move them to another Outlook folder, the mails are retrieved again.
Do you mean that you would have duplicate email messages(the message you moved and the message which was retrieved again) after those specific operations?
I tried the same tests in my Outlook but could not reproduce your issue. In order to conduct further researches on your issue, please try the following suggestions:
- As I know, Outlook send and receive operations are mainly related to the send and receive settings file(.srs). If there is something wrong with your .srs file, issues like this might happen. So, it is suggested for you to delete the the send and receive settings file(.srs) of your email account and re-start your Outlook in safe mode (Press Win + R, type “outlook /safe”, press Enter.) to see if the issue will still continues.
Location of .srs file: drive:\Users\<username>\AppData\Roaming\Microsoft\Outlook - All pop email messages will be cache in your Outlook datafile(.pst). And if the datafile of your email account is corrupted, issues like this might also occur. So, please try to exit your Outlook client and repair your Outlook datafile to see if your issue could be resolved. You could find your datafile via File > Account settings > Account Settings > Data files > Select your email account > Open file location.
Any update, please feel free to post back.
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