I have been using the program for more than 3 years without any worries, but now i have one big problem:
I updated my server last month (debian 9 to debian 10) and upgrade limesurvey to version 4.3.5+200721
I can access without any problems to my web admin space, but when I want to visualize one survey via the web admin space or via direct http link i have this message:
500 : internal server error
Invalid default template directory
Unfortunately LS 4.x has still a lot of issues, this might be one of them.
I currently can not recommend LS 4.x for production yet. Stay with LS 3.x. Unfortunately, you can't easily "downgrade" and you also can't export your surveys from LS 4 and import it into LS 3.
Help us to help you!
Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.