Problem with remote force install

Hi
I'm trying to do update on clients with version 1.7.1 and earlier using remote command

/ForceInstall /VERYSILENT /NOCANCEL /NORESTART /LANG=polish /NOICONS /COMPONENTS=program,ghostscript,image2pdf,languages\polish

if computer don't have previous installation it working, but when i have its problem with reinstalling pdf
could u help me :)