This is the most common problem with blogger templates that when you add some widget, image or link that do not fit the allocated width, the sidebar is pushed or displayed at the bottom of the main content. This problem mostly occur with Internet explorer (IE) versions.

How to solve this?
One obvious option is to find the culprit in the blog design and eliminate it, by repeatative elimination method, where you take out recently added widgets or section of blog one by one until the problem area is found.
This method is again plague with its own drawbacks like time consuming, not always promisable, etc.

There is one other solution that we recently found, that helped me solve the problem and so should work for you.
Since such cases occur because of overflowing pictures, text, link or widget, we need to take care of this overflowing matter in the blog to not cause problem ever.
So to avoid this overflowing problems, find out style definition of your content and sidebar sections in your blog template (style parameters are usually defined in head section of template), it should be something like this

#content{float:left; width:480px}
#sidebar-right{float:right; width:390px}

This style name may differ across different templates, so one possible option is to lookout for width attribute in this style parameter.

Alright once you found out, then add following attributes to both these style parameters (remember to take backup of your template before going on with change)

word-wrap: break-word; overflow: hidden;

so finally the style parameter looks like below

#content{float:left; width:480px; word-wrap: break-word; overflow: hidden}
#sidebar-right{float:right; width:390px; word-wrap: break-word; overflow: hidden}

That's it save your template and see the effect. This should work.
Let me know if you still find any problems.

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