Hi @geetakumar,

Are you able to read in the file successfully or does it error out?

Would you be able to open up the IFC file in notepad++ and check for instance #1154? (Ctrl+F will be helpful to search the file). I'd be interested to see if there are any special characters in that line such as a degree symbol or latin charcacters. If there is a special character in that line, removing it should fix the issue according to this similar question in our Forums. Let me know if that's the case for you as well, thanks!

@jovitaatsafe I am not able to read in the file successfully, it errors out so I can't even see the source data. I have opened the file in notepad++ and checked for instance #1154. It does not have any special characters

What version of FME are you using and would it be possible to share your iFC file to take a closer look at it? You can send it to if you don't want to share it publicly here.

Hi @jovitaatsafe,

I am using FME 2019.

I have sent the file through email.

thank you

Quick recap for anyone else seeking a solution for a similar issue. This particular file had a few validation errors according to KIT's IFC Checking Tool. We ended up using the 12D Model reader instead as the IFC file was exported from that format.

Hi @geetakumar and hi @jovitaatsafe

I landed at this Post because I had a similar Problem. The Same "error ISO10303-21: Skipping instance #####: Instance is not syntactically valid" . I am Novice with the FME Workbench and I am just working on a Project where we have to transform a lot of .ifc to .gdb. means Open BIM to GIS. I also realized that there were already some Workarounds and Solutions posted here after analyzing the IFC file and looking for Solutions. I tried everything and it didn't Work: I didn't have any special characters and I tried another Reader and it couldn't read the File. This situation here made me try to analyze the Problem taking into account the original error statement. Please see the Photo.

I researched more Information from the IFC 2x3 Format. Normally the IFC 2x3 was elaborated just to support the BIM Coordination Models between all the Participants on a Project. (https://www.b-cert.org/Documentation/e6d094e3-7245-45e5-3154-08d500137b53 ) Some Properties of the IFC 2x3 won't be full functional or in other words: There is not benefit to read those Features - In this particular case Properties and Quantity Sets. I decided then to mark it as follow at the Reader Parameter BEFORE closing the Reader in order to run it on the Canvas. Then I ran the Reader and EUREKA !!! it works !!!!

I think another point maybe to analyze is the described Semantic of an STEP Format in this Article : https://www.loc.gov/preservation/digital/formats/fdd/fdd000448.shtml

I hope this can help other Folks with the same problem and same time gives some ideas from future improvements in order to find a compacted solution for all those issues. I have realized that those Problems do not happen that much on IFC 4 files. So that is why I assume it is an issue with the Semantic from the IFC 2x3. On top of that IFC 2x3 is really Old and it had some improvements but it was always a headache at the moment to use the IFC Files in another BIM application cases since the Modell View Definition MVD was only elaborated for just Coordination and from Software to Software it could be a little bit different the transformation Matrix from Autor Software to Open BIM Format aka. IFC. Other important Point : I am not an IFC expert either so please don't overestimate my expertise. :-)

Best Regards

Hi @jrrdm,

Well done and thanks for sharing! I'm glad to hear you got it working and I'm sure others will benefit from your answer as well. (:

Hi, I get the same error message in FME while importing an IFC file.

“ISO10303-21: Skipping instance #859: Instance  is not syntactically valid.”

The referenced line is:
#859=IFCSHAPEREPRESENTATION($,'Body','MappedRepresentation',(#858));

Can you please help me here?

Hi, @yachten.

Have you tried the solutions in this question thread above, from jrrdm or possibly jovitaatsafe?

If so and you are still having issues, can you provide what version of FME your using and provide some screenshots of the issue? Also, if you are comfortable, send the IFC file here?

Thanks.