First thing I would do is to see if my firewall and/or anti virus has been turned off by roguewares.

Then I would try to update then run my anti spyware programs. Run it even if the update is not allowed and see what is found.

You might also consider starting in safe mode - tap F8 during startup - remove the internet cord and run the tests again and see if things change.

What anti spyware programs ar you running and are they up to date?

since something may have got on your pc and shut off some of your programs it is a good idea to do an online scan to see what they find. Here are a couple I suggest you go run on your pc, let them clean anything they find.
trendmicro

malware scanner

let us know what was found and what is happening

My first thought is the file association is improper.

Please, what does the appearing message say in its entirety? Also, right click on one of the previously "good" downloads and click on Properties. On the General tab what type of file is identified?

I do not know of a pp.pdf extension and a cursory review at Google does not report one. I am wondering if the file's creator has inadvertently co-mingled extensions; ppt, pdf and perhaps the recognized abbreviation for pages pp.

DA

I did not recognize it either and did the google search and found only this post showing up. Either some file extensions are screwy or something is causing conflicts.

PDF is the extension for Adobe's Portable Document Format. The pp is just part of the file name (It's a pdf named "May Bag etc pp" with an extension of pdf).

Did you recently install a new program (PDF Factory) and let it be the default for opening pdf files? It's possible that the file is corrupted. It's also possible that it's in a newer PDF format that PDF factory doesn't yet understand. Try right clicking the link and downloading the file to your hard drive, then instead of opening it by double clicking it, right click and select open with. One of the options should be Acrobat Reader (I've got version 8.1). If it's not one of the options, you can select Choose program.

If you don't have Adobe Acrobat Reader, you can get it here.

Another program that reads PDFs is Foxit Reader.

WOW, thanks to all you guys for all your help, it really is much appreciated.

I have checked to make sure the firewall is switched on. In fact the Windows firewall is off but I presume that's because I have McAfee virus and firewall and McAfee says "enabled and up to date".

Also I use CCleaner and Ad-Aware, both were recommended to me by this forum and are used regularly. Thanks again for that too.

Anyway to get to the point, I followed the PDF instructions by bpgreen and I'm very glad to say it worked fine. I already had version 8.1 so it was great. Thanks very much. I have got a free version of PDF Factory and I had a feeling somewhere along the line I'd messed up something.

I use my PC such a lot but am useless on the technical side so I really do appreciate the help I get on this forum. You're a great group.

Many, many thanks for all your replies, Marian

I'm having the same problem here. As of this afternoon, no downloads. I can't figure it out, any help?

Have you followed all the suggestions posted above starting with the online virus scan.

First thing is run your AV, there could be a trojan in your downloader, many ppl have anti virus programs but fail to scan entire PC from time to time which is very necessary...