Dreamweaver creates one for each folder that has had any interraction between local and remote sites, to create its own record of sychronisation details, like a 'cache'. It keeps these in a folder called '_notes' in side each of your site folders.
The quickest way to sort this outside of Dreamweaver (unless you configure an FTP program to ignore terrors) is to open the site folder (My Computer or Window Explorer) and in the search input field (Top right of window) paste 'dwsync.xml'.
This will list all dwsync.xml files, and you can select them all (Ctrl A) and delete them. In PowerCMS 102 there will be 116 of them.
Uploading a site from within Dreamwever using DW's FTP, while very slow, shouldn't error any upoads, apart from (sometimes) just one instance of a message saying it can't find synch info, but you just click Yes or Ok or whatever the opion is to continue. So I don't know why you would get continued errrors, as this would only happen on one occasion (per upload, if at all).
There is no reason, assuming that all the rest of the files and folders uploaded OK, why you should not be able to reach your site and set-up pages, - so I assume that some got missed. The particular error message you got when accessing your uploaded site seems unlikely to be caused by just missing files, though, as the message would just say that it couldn't find the file.
Try deleting the dwsync files and uploading the complete site afresh. Hopefully that should take you forward.
Also worth getting hold of a free FTP program so that you can do transfers outside of Dreamweaver.