It most likely is not their choice.  Size limitations are set by the internet service provider (ISP).  However, they can be changed.  You may want to very politely let your client know of the problem and that they may be able to get that limitation increased by calling their internet service provider. Not all service providers will be willing to do that, but it is worth a phone call to find out.

FYI... 5MB was a typical size limitation years ago.  However, most ISP's have upped that limit with the prevelence of broadband.

That said, a search in excess of 8MB when scanned should be rare.  Check you scanner settings.  You should be scanning, in my opinion, 600 dpi (dots per inch), black and white.  If you are scanning in color or grey scale, your file sizes will be much larger than they need to be.  You could even get away with 300 dpi, which is typical fax quality, but I find 600 is generally better and still results in a reasonable file size. Typically, we can scan about 60 pages and still be safely under 5MB.

The other factor is inverted copies (white text with a black background).  Those result in a much larger file size.  Most scanning applications will have an option to "invert" those (change them to black text with a white background). 

Best,
Robert A. Franco
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