I have no idea what this means. I started off with a new install of with a new install of Unity and this happens.
I have no idea what this means. Hopefully, someone will help.
Read the first line. “The project you are opening has complication errors”. It basically means there’s code errors.
Usually you open in safe mode, work out and hopefully fix the errors, and then Unity returns to normal.
This happened to me as well when I installed Unity 2021.3 on a new system and created a URP or HDRP project. Apparently, the templates use an incompatible URP/HDRP package and this causes the problem. You can enter Safe Mode or Ignore the error, and then it should automatically load the correct package. If not, open the Package Manager and load it manually.
I had this happen when opening a 2022 project in 2023 because of changes to textmesh pro, the errors will guide you, open in safe mode, see what the errors are, fix.