How to change "Read-only" 3D model to normal model?
Try to do a Save As
What John suggested should work but it looks as though you are using Workgroup PDM or EPDM and someone has ownership of this file or you don't have ownership. Therefore the file is read only. See if you can take ownership from the vault or, if someone has ownership, have them release it then take it yourself.
Also check to see if the "Open referenced documents with read-only access" is Checked Off.
It might also be that when it was copied from its original location that Windows Explorer marked the file as "read only".
I have seen this many times when coping from a server or another system.
Close the part in SW. Then go to Windows Explorer and find the file and then right click on it and select the properties.
See if the Read Only box is checked. If so, un-check it.
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