I wanted to use ontape -s to backup to a file.
My database server is still clean (only sysmaster and sysutils)

I get the following error:

informix - /usr/informix>ontape -s -L 0

Please mount tape 1 on /informix/backup/ontape and press Return to continue ...
Archive failed - buc_fe.c : Archive API processing failed at line 242 for msgtype

Anybody any idea?

Check your onconfig file configurations. make sure the tapdev and ltapdev parameters are configured currectly (the size is important, the max is 2G) if you changed parameter - you need to restart your server.
make sure that both files exists ( tapddev and ltapdev)
Try to put full path like c:\temp\data.bak it can be a link
I'm not sure - but make sure the informix has write privileges to the file

Hope I helped.

Dafna

I seems i hit a bug on that one.
I reïnitialized my server and tested again and it worked.