Picasa refers to software of that name.
You might be able to find those scanned documents via the Picasa program system. But if you don't have Picasa installed on your system, then that's not possible.
Anyway, having no desktop icon for your printer is not very severe. What is important is that you have scanning software to use that can produce and store a PDF file. Check on whether you have these:
Start - Control Panel - Printers, locate your printer's icon here - is it present? that's all you need there.
Start - [All] Programs - Canon Utilities - MP Navigator EX
...if Navigator EX is there, you have the software needed to scan to PDF (which cannot be done from a button on the printer; the scan must be mediated by software, and the storing to PDF also.)
When you start Navigator EX, you need to be in one-click mode to scan to PDF.... you will see a PDF icon on the one-click mode window of Navigator EX, like this:
For further instructions on how to use MP Navigator EX to scan to a PDF file, just go to this page:http://www.usa.canon.com/cusa/support/consumer/printers_multifunction/pixma_mx_series/pixma_mx330#ServiceAndSupport
and enter 'scan to PDF'
in the search box, then click the Search button next to the search box.
In the results of that search, click on 'how do I scan with Navigator EX?
', and you'll get two links, one that says 'how to scan with Windows
', and click on that one.
That will give you a long well-illustrated page with instructions on how to do what you're looking to do. It's easy enough.
Let me know if you don't have an icon for your printer driver in the Printers list in Control Panel - or if you don't have MP Navigator EX on your machine. There are ways around those difficulties, and I can instruct you in them.
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