@SERVICE INFORMATIQUE DES ARDENNES
Currently in Microsoft Q&A we only support English, could you please edit your question into English?
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I get the following content via Translation tools.
Do you mean that you could not load data from shared file on server for mail merge in Word?
If yes, is there any error message shown on screen?
Here is a thread, "Mail Merge cannot find data source", maybe you could have a look.
In addition to loading data sources, can you browse and open some shared Office files directly on this server through File > Open in Office apps?
How did you access the shared file on server?
Such as via a mapped drive, the UNC path or others.
If there is a mapped drive, I would like to suggest you unmap it and add the path of the server as trusted locations into Office.
To add Trusted Locations, please go to File > Options > Trusted Center > Trusted Center Settings > Trusted Locations, then please tick the box of "Allow trusted locations on my network", then click "Add new location" to check this issue.
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