Keep Old Permalinks on New Blog?

Host server upgrade kills WP 3.1 blog on Friday. Just installed 4.7.3 to take its place on Thursday night. So far as I know, I need to re-enter all post and page titles and text in “new” blog.

Is there any way to keep the original permalinks when doing this, so existing links remain live?

4.7.3 will not use the 3.1 blog’s database; tried that, nothing but errors–so had to create fresh database…

Thanks for any help!