database, freed up some space by cleaning out some temporary files and restarted the database. As it now had some space to work with, and the archival command worked again, it started copying over all the old transaction logs and eventually cleaned them out and resumed normal operations.
3) What will be done to prevent this in the future?
Various things:
* I will move the main database files to its own drive. This is going to be neccesary in the near future anyways. The transaction