This server folder is an example of how your folder should look like (in terms of):
- /filterscripts/iTD.amx
- /plugins/iTD.dll
- /plugins/sscanf.dll
- /MSVCR100.dll

If any one of the above are missing, it won't work.
Oh and don't forget to add the plugin names to the "server.cfg"

It should look like this under filterscripts line:
plugins sscanf iTD