Internal error while importing csv file
I'm here just to give a solution I didn't find in this forum, or elsewherre, concerning problems of imports of csv files.
The error apperared even before the assistant allowing to match the fields opened.
After looking at the production.log file is /var/log/redmine/default/ (I use Ubuntu as the server), I finely understood that Redmine server was trying tu upload the file I wanted to import into /usr/share/redmine/tmp directory; which didn't exist.
So I created it, giving right to everyone to write in, and the problem was fixed !
Hope that will help someone someday !