Cannot drag and drop files in Finder on Yosemite 10.10

I just opened my new Macbook Pro with Yosemite. Was alarmed by the impossibility of click and drag in the finder (when trying to move an app to the dock it would just open an info window, and when trying to move a vid to a folder it just opened the vid in a preview window), and disgusted to find that people have had to go to dig and devise workarounds to figure out how to restore this functionality (if it were just a setting, OK, but my desktop folder was never locked). I don't know if these factoids will give any clues to the tech-smarter people on here, but:

- The first thing I did in my panic was to plug in my venerable WACOM CTE-640 to see if I could still get click and drag and functionality with the stylus. Yes, thank goodness. Just as before.

- Then tried some cut and paste stuff in TextEdit. Found that if I double-clicked a word and tried to click and drag it, say insert it into the middle of another word, it worked (also works in this [hypertext?] window I'm writing in now. But try to drag-and-select a word in TextEdit and it tries to open Look Up. Try to drag-and-select a word in THIS WINDOW, however, and it works...??

- Copy and paste seems to work just fine in TextEdit (using pull down commands and keyboard shortcuts), despite the click and drag in finder troubles.

Go to work, guys.

Not sure the guys have as much work to do as you, as it's quite obvious from your description that the issue is with your trackpad or mouse settings. When you click you're getting right-clicks.

Thanks jay42k! 🙂

⚠ If the problem reoccurs after restarting, the following worked for me...

I checked to see if the same problem happens when logged in as a different user. Finder seemed to be working smoothly for other users. If this is the case, paste the following line into the terminal to remove the plist file for the problematic user, hit enter, and restart.

rm /Users/USERNAME/Library/Preferences/com.apple.finder.plist

I did this without logging out of the problematic user and all is well.

Please note that the terminal command Jorge gave will delete your Finder preferences file, in case that's not clear enough. Also, note that restarting logs off all users. FWIW I've not seen this problem in some time.

AirParrot 2 was the culprit. Deleting AirParrotDriver.kext & APExtFramebuffer.kext fixed it for me!

- Go to [HD]\System\Library\Extensions

- Delete AirParrotDriver.kext & APExtFramebuffer.kext

- reboot

I just restarted my computer and drag&drop working now. But I believe this is a temporary solution.