opendialog filter for alot of extension

opendialog filter for alot of extension

i work on .Net with c#, on xp computers, using openDialog.Filter, when i
use filter with special name, like "Picture Files", but i got more the 256
chars, in some computers, the extension that come after 256 chars is not
found, if my code is
openFileDialog1.Filter = "Picture Files| *.bmp; *.jpg; *.jpeg;......
*.png; *.tif; *.tiff|All Files ( * . * )|* . *";
whan i run it, and choose the picture files option, i can't see
"png,tif,tiff" files, if its come after the 256 long string. but all the
next options work good, like "All Files", and more type i put after, i try
work with .Net 4.5 but its doesn't help to those computer, did anyone know
why its happend in some XP , but in some XP computers its work all fine?
and how can i fix it? thx ppl.