I have a mesh object that my avi passes through it. I think it was not like that initially. Can I

[examining]

...make it solid?

It's somehting I bought and is supposed to sit on it, step on it without entering or passing through it, such as a house for instance.

Am not sure, but I think initially it was alright but now it is as I describe.  Is there anything I can do?

Thanks

P.S. The phantom  is unchecked, the physics shape is convex hull and yet I pass through the walls.  The only thing I noticed is that, in object, locked is checked before to try to enter, and after having passed through te door instead to open it, locked is unchecked.  The one who sold it to me is not friendly.  If I understand the answer I got is "do not piss me if you want me to fix/replace it before next year".  And it's lots of money I paid.  I do not stop to think that money makes things worse rather than better in SL.

P.S. 2 It's let us say, something like a bus.  Not only about standing and walking on it, but one must not fall outside if he chooses a seat near a window.  Among other things.  I found a satisfactory solution by taking a long road around the problem, as I often do.  Temporarily.  And also, I comfort myself, thinking that 5000 linden and more I paid are only like 20 euros in RL.  Aren't they?

[Rolig Loon]

An object with the property you are describing is called "phantom".  There are at least three ways to change an object's phantom property.  One is to select the object, open your editor, and look for the checkbox labeled "Phantom".  Then check or uncheck it. You can also change that property with a script.  A third possibility, less obvious, is to change its "Physics Shape", on the Features tab in your editor.  That parameter controls how the servers regard the object when they determine how it should respond to collisions.  A standard prim is set to Physics Shape type "Prim" and a mesh object is normally set to "Convex Hull".  It is also possible to set any of the child prims in an object (but not the root prim) to Physics Shape type "None", which means that the servers ignore any collisions with it -- effectively making it phantom.  Changing an object's Physics Shape type may have other side effects -- for example, it can make its Land Impact increase or decrease dramatically, or make it impossible to walk through doorways --- so experiment on a copy of your object in a sandbox. (Take a look at https://community.secondlife.com/t5/Building-and-Texturing-Forum/Phantom-vs-Physics-Shape-Type-None/m-p/2976126 )

Depending on whether you have permission to modify the object, you may be able to change its phantom property with any of those methods.  If not, you should probably contact whoever created the object and ask.

[ChinRey]

There's not much you can do unfortunately. Linden Lab follows a very clear "Buyer Beware" policy and if the seller/maker doesn't want to correct their mistake, there's no way to force them to. But you can leave a negative review if you bought on MP of course.

Three things to remember:

1. There are lots of builders who don't know how to make mesh but still do
2. There are lots of good designers who don't know how to make mesh
3. There are lots of builders who believe they can make mesh but can't

The bottom line is, don't buy mesh objects unseen.

 Edit: In case you wonder what's wrong: I can't say for sure of course but from your description it seems like the maker uploaded the mesh with a faulty physics model - or even with no physics model at all.

[Roche Runo]

You didnt mention what your object is  but if its is something you want to stand or walk on  you can just put down an invisible prim.

Hope this helps.