Yes! Get butterfly anchors. It's a little tricky at first, but once you get it, they're easy to use.

Below is a pic of what they look like. I had the same problem when hanging one of my arched shower curtain rods. These worked wonderfully.

You'll want to get longer screws, so take one of the screws to the hardware store so you can get screws and the butterfly anchor in the correct diameters. Take the hanger, while you're at it!

To install: Drill holes where the butterfly anchors and screws will go in the wall. Fold the butterfly anchor up, and the widest part is the size of the hole you want.

Put the screws through the holes in the hanger, and then put the butterfly anchors on the screws. Spin the anchors on far enough so that you can get it through the wall.

Squeeze the anchors closed again and push them through the holes.

Once they're through and you know the butterflies have opened, pull the hanger back toward yourself so that the open anchors are up against the wall and you can't pull the hanger back any further.

Then, while pulling the hanger toward yourself, screw in the screws.

I would be worried that the hole may need to be too wide for a butterfly anchor and would show at the hook edges...
if you go to most any hardware store and go to their screw dept, you will find the screw width you need in a longer length--- for a few cents you can just buy the 2 screws you need rather than a whole box... if you don't know the width of the screw (the width is a # like 8, 10, 12) bring one you have with you!

Tibbrix, thanks for the rave review of butterfly anchors. They look like they would hold plenty. I'm just concerned about 1) the size of the hole to get all that stuff through, and 2) its visibility under the hook base. There just isn't a lot of room there. It barely covered the anchors that didn't work.

busybee3, I suspect I just need longer screws. It would be nice if they were decent looking up top since it shows, but at this point, I will settle for something long enough to expand the anchor.

I've already patched and painted the holes I made yesterday. It took a LOT of spackle. :) I just couldn't stand to look at them in my nice new bathroom.

Hopefully the friendly guys at Ace will help me out. I'll definitely take my hook with me.

Since you have spackle and paint, try using a molly bolt assembly. Drill appropriate hole, countersink the collar just below surface, spackle and paint over the repair, mount accessory.

Here's what I do when hanging decorative accessories on hollow walls or doors.

Test fit the wall anchor to the back side of accessory.

Snip off visible collar overlap with utility knife or snips.

Drill slightly undersized hole for anchor.

Fill hole with wood glue or adhesive caulk.

Insert anchor and mount accessory.

This method also works on 1/2" and 5/8" drywall.

For an invisible anchor:

Drill wall anchor holes.
Countersink each anchor collar just below drywall surface.
Insert anchor.
Cover anchor hole with screw (two turns is fine)
Spackle, sand and touch up with paint.
Mount accessory.

For now, it makes more sense to stick with what you have and use a longer screw of the same size.

In the future, you might want to try these. I have mounted entire shelving units using them, as well as towel bars and towel hooks.

Here is a link that might be useful: Drywall anchors

From your description, I'm not sure what kind of wall anchor you used. We typically use mollies when we want a strong connection and have only drywall.

IAC, it should be a simple thing to find a screw of the same diameter but longer length. If you're unsure, ask for help. Home Depot type places will have some, but you may be better off going to a Sears Hardware or Ace Hardware or other such place that has a larger selection of screws, and hopefully someone who can help you. Be sure to bring the screw with you so they can match it up.

This post was edited by AnnieDeighnaugh on Sun, Oct 26, 14 at 8:54

longer screws won't help if there is nothing for them to bite into. Toggle bolts, mollies or plastic anchors are made for use in drywall. Depending on the weight (hand towels will need less strength than a robe hook) Small plastic anchors should work for hand towels or light duty. Go with the toggle bolts for more strength. And yes, the hole for the wings will be huge and need some patch/repair as mentioned above.

You can use the ones Graywings recommended
When the anchor is in the wall
paint it the wall color for less viability.

OOPS did I just type viability ?
You know I meant less visible :)

This post was edited by forboystoo on Sun, Oct 26, 14 at 16:15

Everyone, thanks so much for your help. I just learned how molly bolts work. I had wondered about the screw it came with. Who knew you take it out?

Graywings, I have been using (and loving) E-Z Ancors for stuff like curtain rods. They're so much easier than tapping plastic anchors which will bend and collapse if you look at them wrong. The problem I'm having is the screw isn't long enough to trigger the expansion of the anchor.

Next time I will paint the top circle thing of the anchor.

What's the best method for countersinking a molly?

What's the best method for countersinking a molly?

Countersinking isn't needed for most applications, but when it is....

Use a flat blade screwdriver that matches the diameter of the colllar. Tap an X over the hole and applying slight pressure twist the driver to cut away enough gypsum to countersink the collar.

brushworks, thanks for that tip!!

Out of curiosity, where are you putting the robe hook? I have often wanted one right next to my tub.