go to navbar and find something like that and delete it:
Code:
<td nowrap="nowrap" style="padding:0px">
<form action="login.php?do=login" method="post" onsubmit="md5hash(vb_login_password, vb_login_md5password, vb_login_md5password_utf, 0)">
<script type="text/javascript" src="clientscript/vbulletin_md5.js?v=374"></script>
<table cellpadding="0" cellspacing="3" border="0">
<tr>
<td class="smallfont" style="white-space: nowrap;"><label for="navbar_username">username</label></td>
<td><input type="text" class="bginput" style="font-size: 11px" name="vb_login_username" id="navbar_username" size="10" accesskey="u" tabindex="101" value="username" onfocus="if (this.value == 'שם משתמש') this.value = '';" /></td>
<td class="smallfont"><label for="navbar_password">password</label></td>
<td><input type="password" class="bginput" style="font-size: 11px" name="vb_login_password" id="navbar_password" size="10" tabindex="102" /></td>
<td class="smallfont" nowrap="nowrap"><label for="cb_cookieuser_navbar"><input type="checkbox" name="cookieuser" value="1" tabindex="103" id="cb_cookieuser_navbar" accesskey="c" checked="checked" />remember me?</label></td>
<td><input type="submit" class="button" value="Login" tabindex="104" accesskey="s" /></td>
</tr>
</table>
<input type="hidden" name="s" value="" />
<input type="hidden" name="securitytoken" value="guest" />
<input type="hidden" name="do" value="login" />
<input type="hidden" name="vb_login_md5password" />
<input type="hidden" name="vb_login_md5password_utf" />
</form>
</td>
</if>
</table>
*make backupfile