[Self-solved, NOT a TL issue] Can't do XML inport

[larsen]

I export from one 1.9.15 server into a 1.9.16 server using xml.
When importing I only get a blank import window and no data imported.
New installation.
I get "E_WARNING file_put_contents(/development/var/tracer.log): failed to open stream: No such file or directory - in /srv/hwtir/testlink/lib/functions/tlFilterControl.class.php - Line 268" from time to time but not directly related to this event.
Installation / Configuration problem? I guess the upload_area dir is used, I the access rights is 777. No spaces in filename. It's ok to create Test Suites / Test Cases inside TL.

[fman]

there is a debug line trying to create a file in an non existent folder => remove the file_put_contents()

[larsen]

Solved!
Php xml was not installed.