It is beyond frustrating to have window blinds that refuse to raise or lower no matter what you try. Don’t keep yanking on those cords, because you might do more damage than good. ForRent can help you fix broken blinds within minimal fuss.
The cords may still hold the key to fixing those blinds. Just make sure you tug gently on them as this loosens the blinds. You’ll also want to hold them level with the headrail as you pull to get them to lower.
If this doesn’t work, then the cord lock could be the problem. Fixing that requires taking the blinds out of the window, which you can do by removing them from the brackets. Set the blinds on a counter or table to more easily inspect them.
To locate the cord lock in the headrail, look for the mechanism each of the cords run through. You should also see a pin. Use a flathead screwdriver and place it perpendicular to the headrail to press down on the pin. This will disengage the cords.
The blinds should now raise and lower just like when you first bought them. Congratulations! A successful home repair!
*We can’t promise you that the following techniques won’t get you in trouble with your property manager. Before you start any of these projects, make sure that you get written permission.
from Apartment Living Blog https://www.forrent.com/blog/diy/how-to-fix-broken-blinds/