Hello,
Anyone got any ideas about this.

I am trying to setup OS Authentification.

WHen I connect I get the error:
ORA-01004 default username feature not supported; logon denied

The oracle documentation is no help.

Its 8.0.5 NT
My pfile is correct it looks like:
db_name = lap
db_files = 1020
control_files = ("E:\orant\database\ctl1lap.ora", "E:\orant\database\ctl2lap.ora")
db_file_multiblock_read_count = 8
db_block_buffers = 200
shared_pool_size = 11534336
log_checkpoint_interval = 8000
processes = 50
dml_locks = 100
log_buffer = 8192
sequence_cache_entries = 10
sequence_cache_hash_buckets = 10
#audit_trail = true
#timed_statistics = true
background_dump_dest = E:\orant\rdbms80\trace
user_dump_dest = E:\orant\rdbms80\trace
db_block_size =4096
compatible = 8.0.5.0.0
sort_area_size = 65536
log_checkpoint_timeout = 0
remote_login_passwordfile = shared
max_dump_file_size = 10240
remote_os_authent=true
os_authent_prefix=""

############### Oracle replication ########################
global_names = true
job_queue_processes = 2
job_queue_interval = 60
job_queue_keep_connections = false
distributed_lock_timeout = 60
distributed_transactions = 16
open_links = 4
snapshot_refresh_interval = 60
snapshot_refresh_keep_connections=false
snapshot_refresh_processes = 2