I am installing moonlight-plugins on firefox to use GIS explorer.
The shell reply to me that I have to install several things first, but this is what I need

root@pntl:~# dpkg -i labavcodec52_0.6.2-1ubuntu1.1_amd64.deb
dpkg: error processing labavcodec52_0.6.2-1ubuntu1.1_amd64.deb (--install):
cannot access archive: No such file or directory
Errors were encountered while processing:

What should I do?