The LDB file is one the is created when you open the project
and it should get deleted when you close it. The project has a
database in a CPD file. It is a Microsoft Access database and the
LDB is created by that. It means Locked DataBase. You can delete it
in a closed RH project but don't delete it in an open project, I
think it will not allow that but not sure.
If you cannot open a new project, then something is wrong
with the installation. I don't think it is to do with activation as
that would tell you it was refusing to open until you activate.
If after a reboot you still cannot create a new project, then
try a reinstall, unless of course you are trying to open a project
across a network. If you are, projects must be local.
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