What program is the model being exported from?
If possible have the originator send you a Parasolid format.
The software which created the STEP file may not have created it correctly.
Do you see the parts in the assy?
What size is the STEP file?
Can you upload it for testing?
What is size of the step file. Can you upload that here to have someone check that.
Kelvin you beat me over here by time but we are pointing to almost same thing.
How many parts are involved?
Can you upload a single, non-classified, imported part?
Can you post an image of just the Feature Manager, with some parts expanded to show their features?
Two possibilities I can think of;
1) The STEP file is corrupt.
2) You computer specs (or settings) are insufficient to handle the STEP file size.
when i open the part into SW there is nothing. It is like opening a new part.
There is a chance that you are importing a file that has curves only. Look at your step options and be sure that "surface and solid entities" is checked.
Or the opposite could be true so also check "free point/curve entities"
If these settings are checked and still nothing shows as Kevin said you may need to look to the originator of the file and have it sent with some different settings.
Try it on another machine. I have seen this once recently. Two offsite machines could do the conversion, but mine crashed.
For the empty files - check your import settings against what you know was exported. OPEN / STEP / OPTIONS (button).... For example, if you are importing a file w/ free point curve entitites, but this is not checked, this could be a source of empty files.
If they are from SW then do you not have the access to original files, or is the step file from a newer version than you have?
As the others have noted, make sure that even on the export the proper geometry is included, so surfaces, solids etc.
I have seen this but normally as others have noted either the file is corrupt, not exported properly or possibly copied and given to you before the export was completed....making acorrupt file.
Hard to help without trying the file.
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