I had a similar experience after a "tech" at DLink had me reset some settings so I could remain connected to the 323 after reboots. Well, it turns out that when I went back to a secure way of using the 323 (after I realized that the tech's changes opened up the 323 to ANYONE on the network) all of the files I accessed/changed before were completely inaccessible. I tried everything but could not regain permission to do anything with the affected files. I had to install a hacked version of the firmware, telnet in, and get a UNIX-geek friend of mine help me fix the permissions from a command prompt. That was a lot of fun.
Oops, I see another post just addressed this as well. I'll just add that you don't need to do the fonz thing, you can just download and install the hacked firmware that is identical to 1.05 but has telnet enabled. I found that to be much easier than installing the fonz funplug.