When you're in the Theme Editor in WP, is the "Update File" button available at the lower right of the editor screen? If it's not available, then your permissions for those files are not set (or are not set correctly).

To correct this, you will need to either go into your hosting account's control panel and change permissions for your theme's files that you plan to change, or you could download something like FileZilla (if you don't already have an FTP program) and locate the files and change the permissions that way.

I believe that when the files are loaded via Fantastico scripts, the default is 666 (or RW-RW-RW-). This will allow you to edit those files from within WP. But it's always important to create back ups of each of those files. I constantly save via FTP to my hard drive as I go along editing.

Also, when editing, I often will "comment out" items that I don't want. For instance, if I'm not using widget and I'm editing the sidebar and the calendar is part of the sidebar; rather than deleting the code for the calendar, I will simply place comment codes around it. That way if I decide I want it in the future, the code is still there and I can simply remove the comment codes.

I hope I made sense.

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Jeanne
NowAssistingYou.com
Virtual Assistant :: Web/Blog Design & Hosting :: Writer