. Try uninstalling Windowblinds, run CCleaner or something similar and reboot. Reinstall Windowblinds and reboot again. Check the about link in the config window and see if the problem persists. If it does in the Windowblinds config window click on the about link and post that info here. Also send an email to support@stardock.com with a link to this thread.

Not friends, not solved the problem with these instructions they gave me. I'll have to contact the support department to see if they help me. thanks

Finally someone who understands me! I tried the 8.1 beta version and I feel the same ... still no solution 
Too bad I have not received any help from stardock support.

Have had the same problem, have fond a fix, if you are running nod32 try to disable HIPS. I found this fix works for me, and have found it buried on this site.

For anyone having this issue that has ESET antivirus installed, please try the following.

1) Open the configuration window for ESET, click on the setup option.
2) Then under Computer you should see something called HIPS with a green dot
and enabled next to it. Click on enabled and pick setup from the menu.
3) On the Advanced setup screen find the configure rules button and click
it.
4) Then click new... at the bottom
5) Give the rule a name like WindowBlinds and set action to ALLOW.
6) Then on the source applications tab pick Add... and browse to the
WindowBlinds directory and select wbcore.exe
7) You do not need to configure any of the permissions on
the other tabs, but if this still does not work then just tick them all.
8) Then click ok on each of the dialogs and sign out.

When you sign back in you should find WindowBlinds 8 working and no longer producing the error.