Unable to select IMAGETYPE 'PNG' error

[Sangho Kim]

Hi all,

This is the first time I am sending my question to mapserver forum.
I installed mapserver correctly and try to run workshop demo.
If I initialize the 'Basic Application' of Itasca demo,
it turns out that

msPostMapParseOutputFormatSetup(): General error message. Unable to select
IMAGETYPE `PNG'.

I searched forum archives, but there is no clear answer.
Someone suggested to convert symbols/ctyhwy.gif to symbols/ctyhwy.png
and pinpoint it, but it's already there and pointed in the map file.

Someone suggested to run ./mapserv -v to see OUTPUT=PNG.
But, when I run ./mapserv.cgi -v, I see

ld.so.1: ./mapserv.cgi: fatal: libiconv.so.2: open failed: No such file or
directory
Killed

error message. Due to the webserver configuration, I changed mapserv
to mapserv.cgi.

Someone suggested to change the IMAGETYPE in the map file to
one of the supported formats. So, I change PNG to JPG or GIF.
Now I see

msLoadMap(): General error message. Undefined overlay symbol
"symbols/ctyhwy.png" in class 0, style 0 of layer ctyrdln3_anno.
msAddImageSymbol(): General error message. Unable to load PNG symbol.

I think many forum users encountered this problem.
If someone can help me, it will be very helpful to me.

Sangho