Assuming that you are opening a bookmark, right-click that bookmark and select Properties, then un-check the preference for Load this bookmark in the sidebar, and then click Save.

Using JavaScript buttons on web pages for "Bookmark this Page" causes that preference to be selected when saving the bookmark in that manner. So, don't use those buttons, use the "Bookmark this Page" feature that is built into Firefox instead.

Let me reword this.

I am not opening a bookmark or bookmarking a page, or doing anything remotely related to Bookmarks. All I am doing is reading webpage A, and then clicking on a hyperlink on webpage A. Then, when linked webpage B opens, webpage B displays the Firefox Bookmarks as a left/vertical sidebar.

I neither need nor want the Bookmarks sidebar (on webpage B). If I click on View/Sidebar/Bookmarks of webpage B, there is a checkmark present (Note: I did nothing to put that checkmark there in the first place.) If I "uncheck" /Bookmarks, the sidebar disappears. However, I do not want to have to "uncheck" /Bookmarks ... just as I do not want to have to click the X on the sidebar to remove it. This is the extra step I now have to do.

What is causing the Bookmarks sidebar to 'automatically' appear on webpage B? Is there a Firefox setting (or Windows XP setting) that will override and prevent sidebars from opening automatically on a hyperlinked webpage?

(Note also that on webpage A, prior to clicking the hyperlink, I clicked on View/Sidebar/Bookmarks and there was no checkmark next to /Bookmarks)

Thanks

MB

Can be caused by http://kb.mozillazine.org/Corrupt_localstore.rdf