This is my first project with ZBrush, so please forgive me if this is a “noob” question. I’ve created this model, and am trying to use the ZRemesher to lower the poly count, but it keeps telling me there is an error, (Remesher error encountered) but nothing else. I’m assuming it’s because of the concave areas of the mesh? Is there any way to fix it? I’ve tried adjusting some settings, but get the same error every time. Thanks in advance!
Polycount of the object in question?
Try reducing it to a lower level of subdivision, and ZRemeshing that. ZRemesher will choke on an object if the polycount is too high. Always keep a duplicate of the original high poly mesh to project lost detail from.
Otherwise, assuming a reasonable polycount, the geometry has become problematic in some way, and will need to be “cleaned”. Try doing a Tool > Geometry > Mesh Integrity > Fix Mesh on it. If that doesn’t solve the issue, try dynameshing it at a a high enough level of resolution to keep fine details like fingers separate, and zremeshing the resulting mesh.
You mention you’re trying to reduce the polycount. Note that Zremesher will reduce the polycount, but you will also lose detail with the lower poly mesh, unless you subdivide it sufficiently back to high poly level and re-project the lost detail from the original. If you’re done with your work and aren’t concerned with topology, but simply want to reduce polycount while keeping detail in order to ensure portability between programs, that’s generally what decimation is used for.
Otherwise the point of Zremeshing is usually to create a new base mesh with evenly distributed polygons for good sculpting performance, that will then be subdivided again sufficiently to recapture the lost detail through projection. It isn’t a magic solution to reduce polycount in itself, though it can be used to help create a more efficient mesh that delivers polygons where they’re needed, and away from areas that don’t.
Yea I was trying to reduce the poly count of the full mesh. I am working on a game asset and was going to bake the detail down into maps. I’ve tried all the suggestions you listed (thank you!) but nothing seemed to work. I’ll probably have to take into topogun and reduce it there. Was trying to find an easier way 
To clarify, you dynameshed the model into entirely new geometry, and it still returned a Zremesher error?
That’s…odd. Can you successfully use ZRemesher on other objects?
actually no, I get the same error every time. I tried it on a simple sphere and it gave me the error.
I uninstalled and re-installed the trial and it appears to be working now.
OK, take that back, it’s still doing it
Ok, that’s good news though. If ZRemesher refuses to work on any polymesh 3d object ( test multiple Lightbox premade objects to make sure), you know it’s something borked with your installation, and you dont have to drive yourself crazy troubleshoooting your mesh. You have to drive yourself crazy troubleshooting something entirely different…
When you install the trial, are you :
Disabling any running antivirus?
If on Windows, are you running the installer as an administrator?
If not, reinstall while doing both of those things.
Is the installer an up to date version containing the P1 patch, or are you running the updater for any reason?
If Zremesher still refuses to work on any mesh without error, and you are unable to correct the problem through uninstall/re-installation, then you’ll have to contact support and have them sort it out.
I did try all that again and it didn’t work. Version 4R7 was the download for the trial, but I received my 4R8 license today and now everything works as expected.