Redmine

Your screenshot does not show any details of an internal error in Redmine. Please check that you have provided the right screenshots and add more details about the issue you are experiencing, specifically a description of what exactly you are trying to do, and how exactly the error manifests itself. A clear way to reproduce the issue and verbatim error messages are most helpful in any case.

Create issue, paste blue text from screenshot into description, click create, get internal error. As I said above.

Ah, that makes it a tiny bit clearer.

In general, Redmine does not define any not allowed characters in the description (or any other field). However, depending on the database and database settings used by the Redmine server administrator, some characters may be disallowed of they can not be stored in the database used. This was once common for older MySQL / MariaDB databases using their 3-Byte UTF-8 encoding in text and varchar columns.

However, to find why this fails, you (and we) would need an excerpt of the server logs which are available to the Redmine server admin in logs/production.log in the Redmine server. If you are not a server admin, please ask the server admin to have a look there.

The guy from the hosting company said that he was able to see the problem. The database guy is going to fix the problem by changing something on the database. I hope I can get more information when the change has been done.

After the database was updated I haven't had any errors so far.