404 error when using rewrite engine

[eluser]walrus_lt[/eluser]
Hello, i am getting an 404 error when using rewrite engine when i am accessing, http://localhost/projects/ but when trying access http://localhost/projects/welcome/ then everything works fine. What's the problem?

Code:

<IfModule mod_rewrite.c>
    DirectoryIndex index.php
    RewriteEngine on
    RewriteCond $1 !^(index\.php|google254b42e34114b586\.html)
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteRule ^(.*)$ ./index.php/$1 [L,QSA]
</IfModule>

<IfModule !mod_rewrite.c>
    # If we don't have mod_rewrite installed, all 404's
    # can be sent to index.php, and everything works as normal.
    # Submitted by: ElliotHaughin

    ErrorDocument 404 /index.php
</IfModule>