Suddenly need password for Playbook-USB connection

I've run into a problem the most recent time I tried to copy files between my computer and Playbook.

As background, I should mention that when I first got the Playbook back in late 2011, I set a WiFi filesharing password... and then promptly forgot it. My understanding is that the only way to fix this is to do a security wipe. However, I've always been able to copy files between my Playbook and a computer via USB without issue, even after losing my password (because the system didn't ask for it). The last time I successfully did this was July 2013.

However, when I tried to access it via USB this past week, I am suddenly being asked for a username and password. When I type \\169.254.x.x into the Windows Run dialog, I get an Explorer window titled "Samba (localhost) (169.254.x.x)" with two network folders: certs and media. When I try to go into either one, I get a username and password prompt. It didn't do this before.

So, two questions:
1) What has changed that I suddenly need a password for USB connections, and can it be changed back? (Just before this happened, I upgraded my Playbook OS software to version 2.1.0.1753 - could that be it?)
2) If not, is there any way for me to copy files to and from the Playbook without doing a security wipe?

BTW, the reason I need to use the \\169.254.x.x method of accessing the Playbook is because for some reason, my computer has never been able to mount the Playbook as a drive letter when I connect it via USB. My Playbook's auto-mount works fine on other computers, though.

The reason why I'm trying to copy the files now is because I bought a bunch of $0.99 movies on the PB video store on Black Friday weekend, but they won't all fit in the 32GB storage space, and under the terms of the deal I need to download them by January 1st. This means I'll need to swap the movie files back and forth between my computer and Playbook as I want to watch them.

Any help would be appreciated. Thanks.

Understand about the movies, too good a deal to pass up. You could put them up in skydrive. Then d/l to pc if you want.

Will it let you toggle password protect to no?

Instead of trying to access your Playbook from your PC, you can try accessing your PC from your Playbook to transfer files. Ghost Commander, a free app in app world, will allow you to do this, though it might be easier doing it using either of the sideloaded apps ES File Exp[lorer or X-Plore File Manager. To use any of these apps you'll need to set up file sharing on your PC. There are also a few paid apps in app world that will; allow you to transfer files using their dedicated servers running on your PC

Gooseberry: No, it requires me to input the current password in order to turn it off.

pacoman: I've tried using the Windows Share feature in Ghost Commander, but I always just get a "failed to connect" error. I couldn't find a useful guides to using it, though, so I might be doing something wrong. Am I supposed to put my Windows login username & password in those fields in GC?

Try a username of guest without a password. Also, go into Windows Network and Sharing center and make sure sharing is turned on.