Can you attach the *.sldprt file here?
In 14 yrs of using SolidWorks - I have never had a "big and complicated sketch".
I have had some pretty complicated parts though, generated from small and simple sketches.
- keep sketches simple, usually fewer than 10 entities.
- pattern features rather than sketch entities (usually) if possible.
- usually add fillets as features rather than in sketch.
Thank you so much John.
"It seems impossible to find the error in my big and complicated sketch.
Is there any command or something to show the errors?"
There is your problem...
Make small uncomplicated sketches...
Solidworks will like you more...
Thank you J. Mather, John and David,
I split my sketch to several sketches, and now I am friend with SolidWorks again.
Have you tried SketchXpert?