On a Vista system while performing an uninstall of Symantec Endpoint Protection 11, the uninstall would not complete because of an Error 1606. Could not access network location \\myservername\public\pictures. The location it reports could be different in other cases. I believe in my case it is because I set my systems path to pictures to be on a home server where I kept pictures (but since change the path on that server). So the path was not accessible. Based on a Microsoft KB document that described a similar situation I tried something and it worked. I did a search on the registry for the missing path. Start>Run>regedit and then Edit>Find and I entered the missing path. In my case \\myservername\public\pictures. In each case when the path was found I changed it to %public%\pictures. Keep in mind this is Vista. On XP you might want to use %AllUsersProfile%\path to whatever. This document may explain it better. In the end by replacing the invalid path referenced in the registry with the valid path, the uninstall was able to complete.
Keep in mind to be careful editing the registry and have a look at the documents linked to above for more thorough information. The bottom line is replacing the incorrect path with a correct path seems to fix the problem.