Despite your past success with this format, I'd very much recommend against using WMVs in Premiere Elements -- especially in version 8, which is a particularly clunky version of the program.
Where are these WMVs coming from and what resolution are they? You might be better off using the original files you created these WMVs from or even converting the WMVs to a more compatible format.
Thanks, I'll try converting the files to something else and try again.
Is there a version of PRE that you would recommend I upgrade to?
Unless you buy from the used market (caution... LOTS of warnings around the forum about fakes on eBay) you may only buy the current version... which is 11
Version 11 is excellent, especially on Windows 7!
But it still doesn't play well with WMVs.
You still haven't said what your workflow is and why you're even dealing with WMVs, but I recommend you save WMVs for working with Microsoft products.
Meantime, you'll find information on using Windows MovieMaker 2.6 to convert WMVs to DV-AVIs in the FAQs to the right of this forum.
I typically record MPEGs with a video camera, which I've never had a problem importing. I will occasionally include outside footage, either filmed by a friend or downloaded from YT with permission, and those will often be WMV. Never had a problem before today, though I'm thinking now that the audio download and uninstall alerts might have been coincidental. It seems to be incorporating the AVI files fine.
WMV's should Import on most Windows machines, though if one has upgraded the OS, they might need to install one of the MS CODEC packs (one of the only CODEC packs, that I can recommend).
Still, as Steve points out, WMV's while supported in PrE, are tough to edit, and require a lot of processing horsepower. I try to avoid them at all costs, where possible, and convert, if they are the only option.