Go to Start –> Run and copy and paste the following command:
rundll32 zipfldr.dll,RegisterSendto

Wasn’t that easy?

Go to the offline files tab in windows explorer, hold down  ctrl+shift at the same time that you click the “Delete Files…” button. I know it’s kind of an unusual method for Windows but it does seem to solve the problem most times. It should pop up with a warning message and Yes or No buttons. Click Yes, reboot, and resync and all should be well.

If not, try the following (although I can’t say that I’ve tried it myself):

1. Disable Offline Files with  csccmd.exe /disable

3. Reboot into Safe Mode and delete all content under %SystemRoot%\CSC

4. Reboot again and re-enable Offline Files.

After this is done, try the Ctrl+Shift+click method again.

Also, be aware that the offline file database has a path name limitation. I don’t know what it is – but if your path\file name is too long it will corrupt the database and cause the “The Parameter is Incorrect” error.
Make sure that your file and folder names are kept reasonable. I also recommend not using special characters for any folder or file names.

Hope it helps!