Installation files for Adobe Acrobat XI

Try this:
Install Adobe Creative Cloud software: https://helpx.adobe.com/download-install/using/download-creative-cloud-apps.html
Connect it with your Adobe ID, the one that owns your Acrobat XI license.
And you should see Acrobat XI appear in the applications available for download.

Acrobat XI comes with 31 languages, on Mac they are all installed straight away, on Windows you just have to request an additional installation to add other languages (default is US-English + your locale).

Preferences : Language

This screenshot is from today:

Unfortunately, support lied to you to get rid of you, rather than telling you Adobe's policy truthfully. Apparently, they have been told not to lie in this way, but the appalling behaviour continues. There is no support for old downloads here. The product is past end of life. This shows the importance of carefully keeping all purchased downloads and disks (not just leaving downloads on your old computer).

Contact Adobe. They have removed all downloads for old versions. Sometimes they will give you a download, but it is often English only, and mostly they refuse.