Jazzwhistle wrote:
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I’m also using a static IP
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Thanks a lot, I think this is what finally made it! 
I had tried it before, but it is important to also set the router to always use the same IP address for the MBW. So, now the router is set to always use 192.168.1.68 for the MBW, and the MBW is set to use 192.168.1.68 as well (Basic Mode > Network > Network Mode: Static).
Now I’m just waiting for the indexing to finish and backup of ~150 GB to begin… 
