How did you fix it in your case?
Can't remember. It was probably importing a truncated perch DB and putting it in place of the new DB install.. and then running the install again or creating the admin user manually directly in the db.
Despite host update by OVH to their latest offer, I still have the exact problem when installing Perch...
If I want to create manually the admin user via phpMyAdmin, how can I do that, specially setting the password and other parameters?
It doesn't look to me like this is going to work. I don't think Perch is compatible with your server.
I've created manually the user via phpMyAdmin and it worked. I can now use Perch normally, create and update users, regions, etc.
This problem is not very usually face by the users but I also face this problem then I contacted to https://geek-squad.us/geek-squad-support/ but I did not get the solution for my issue then I contacted to Perch team and they help me to resolve my problem.