Permalinks issue after migration

Hi,

I’ve recently switched my old website to a new domain and server. But the migration was not totally successful: unfortunately most of my link names (not all) on my new website have not been replaced right after migration and still carry the link name of the old domain. So the links work, but they just redirect to the old site.

I found out, those link names that have been replaced automatically and successfully during the migration process with the name of the new domain, were the ones that I created in my WP dashboard under “posts”. But those sites that I created under “portfolio” still link to the old website.
This most certainly has to do with my permalink structure: in my old website I created a permalink for my portfolio posts and therefore replaced the link name “portfolio-items” with “destination” in order to make my links more attractive. Now it’s exactly those “portfolio” sites that still carry the link name of the old website on my new domain after the migration.

My tries so far:
1) I thought I can solve it simply by replacing the link names in my sql-file. But this option (tried in several different ways) doesn’t work and would just always destroy lots of other things on my new website.
2) My WordPress version, as well as all other plugins and themes are updated and were also updated before the migration. So this shouldn’t be an issue.
3) I’ve read it might be an .htaccess error. But my skills for fixing that are too limited.

Replacing all those old link names manually would take weeks or months, since my site and content is so huge. Besides the fact it’s not throwing light on this problem, I’m pretty sure it would also cause errors in the future.

So, if anyone here can help me, your expertise and (paid) support is highly appreciated.

Best,
Mike

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