hi AapoRantalainen, thanks for your help. i find the terminal show a lot of command, it is:

~ $ mypaint
external python-simplejson
confpath = /home/user/.mypaint/
device change: TSC2005 touchscreen <enum GDK_SOURCE_PEN of type GdkInputSource>
Traceback (most recent call last):
File "/opt/mypaint/share/mypaint/gui/filehandling.py", line 323, in save_cb
self.save_as_cb(action)
File "/opt/mypaint/share/mypaint/gui/filehandling.py", line 380, in save_as_cb
self.save_file(filename, **options)
File "/opt/mypaint/share/mypaint/gui/drawwindow.py", line 40, in wrapper
func(self, *args, **kwargs)
File "/opt/mypaint/share/mypaint/gui/filehandling.py", line 249, in save_file
thumbnail_pixbuf = self.doc.model.save(filename, feedback_cb=self.gtk_main_tick, **options)
File "/opt/mypaint/share/mypaint/lib/document.py", line 332, in save
save(filename, **kwargs)
File "/opt/mypaint/share/mypaint/lib/document.py", line 397, in save_png
pixbufsurface.save_as_png(self, filename, *doc_bbox, **kwargs)
File "/opt/mypaint/share/mypaint/lib/pixbufsurface.py", line 115, in save_as_png
alpha = kwargs['alpha']
KeyError: 'alpha'
Error in sys.excepthook:
Traceback (most recent call last):
File "/opt/mypaint/share/mypaint/gui/gtkexcepthook.py", line 169, in _info
dialog.get_content_area().pack_start(details_expan der)
AttributeError: 'gtk.MessageDialog' object has no attribute 'get_content_area'

Original exception was:
Traceback (most recent call last):
File "/opt/mypaint/share/mypaint/gui/filehandling.py", line 323, in save_cb
self.save_as_cb(action)
File "/opt/mypaint/share/mypaint/gui/filehandling.py", line 380, in save_as_cb
self.save_file(filename, **options)
File "/opt/mypaint/share/mypaint/gui/drawwindow.py", line 40, in wrapper
func(self, *args, **kwargs)
File "/opt/mypaint/share/mypaint/gui/filehandling.py", line 249, in save_file
thumbnail_pixbuf = self.doc.model.save(filename, feedback_cb=self.gtk_main_tick, **options)
File "/opt/mypaint/share/mypaint/lib/document.py", line 332, in save
save(filename, **kwargs)
File "/opt/mypaint/share/mypaint/lib/document.py", line 397, in save_png
pixbufsurface.save_as_png(self, filename, *doc_bbox, **kwargs)
File "/opt/mypaint/share/mypaint/lib/pixbufsurface.py", line 115, in save_as_png
alpha = kwargs['alpha']
KeyError: 'alpha'


thanks again!

weechia