Clueless with this little bug

Question

I'm a little loss with this error. I really don't know where to start but, i'll try to give as much information as possible. I'm hoping one of you gurus can shed some light to the topic.
I have a page where I initially check if the page loaded from a post, with the following code:
if (request.getMethod().equalsIgnoreCase("POST"))
now the post is suppose to come from another page. The reason why I check if it's a post, is if in case a user tries to access the page without going through the first page that posts to it, i redirect it
so the if statement goes with an
else {
response.sendRedirect("firstpage.jsp");
return; }
if it's a post i continue drawing the page and showing my form. Now there are no problems when I send a post from firstpage.jsp. But the problems arise when I test my code by trying to go straight to the page by typing the address in my browser. I don't get a Java error but a microsoft internal browser error (ie 5 until now). I noticed that the error ocurs while loading an image from my header of the page. If it helps, my header is inlcluded.
Now I tried commenting the if statement, and everything loaded fine, even if try to go directly to the page by typing the address, but then I don't get to redirect. I'm really at lost here, can someone give any idea what it could be?

Answer 1

Ok now this is becoming annoying. I mentioned above that I took of the alpha code for my image links and everything worked fine. Well I made a new page and I have similar code. It looks like this:
if (request.getMethod().equalsIgnoreCase("POST")) {
// some validations with beans
if ( valid ) {
// some bean procedures
response.sendRedirect("newpage.jsp");
return; }
else {
// display invalid message html embedded }
the rest is HTML below.
The microsoft internal error occus when I load my left menu. My left menu is an included jsp file. Basically it checks who the user is and displays the appropriate menu. The POST comes from the same page. I have similar pages with this kind of design and everything runs fine. Does anyone have any idea why I get an error?
My page is basically divided into 5 parts. The whole page is made of a 3 X 3 table. The first row's columns are merged and the make my header. I include a Header.jsp. In the second row, the first column is the left menu, again another inluded jsp file. The 2nd column in the middle is my body, which contains the code above. The 3rd column is the right menu, which is currently empty. Last row's columns are merged and is the footer with another inluded Footer.jsp file.
I viewed the source when I got the error, the page seems to break in the middle of my LeftMenu.jsp. I was able to load the menu option, but when I reach the links, the HTML gets cut. I finished loading the header, but haven't loaded the rest of the parts of the page.
I really hope one of you gurus can point out what I'm doing wrong. I have pages that are the same, and things go fine. I'll go run through the code again, thanks again for all the help.