Wordpress sidebar missing on index.php

If you go to my main blog the sidebar is missing and the background color is wrong, but if you go to any of the actual posts everything looks correct.

Main page (wrong):

Post page (correct):

I don’t know of anything I changed that could have caused this. One thing that did happen was wp-cache corrupted my index.php cache and the page wouldn’t load at all. I contacted dreamhost about that problem and they deleted the corrupted cache of this page and the page started loading, but it doesn’t look correct. The dreamhost help doesn’t know what’s causing my current problem and suggested I post here. I don’t know if my current problem is related to this wp-cache thing, but since it happened at the same time I thought I’d mention it. I have now deactivated wp-cache, but I don’t know how effective that is.

Does anyone have a recommendation on some files I could try restoring or other idea that might restore the sidebar on my blog’s main page?

Let me know if you need any additional info.

Thanks in advance!

Hmm. Perhaps go to the Theme Editor (Login as Admin, go to Design section, Theme Editor), look at the Main Index Template (index.php) and see if the line

<?php get_sidebar();?>

is present towards the bottom?

I think that is the command that calls out to the sidebar sheet.