i got my folders shown in the content browser, no fbx shown aside in the other /new content browser window.
the fbx are shown also in the viewport and in the scene outliner…
It’s possible your redirectors got mixed up somehow. Please try right-clicking on the folder containing your missing fbx files, then selecting ‘Fix Up Redirectors’.
If that doesn’t work, try right-clicking on your asset (either in the level or in the scene outliner) and select the ‘Edit’ option. Then, in the Static Mesh Editor, click the ‘Asset’ dropdown (next to File/Edit in the toolbar) and select Reimport to reimport the asset.