Handling the model causes the program to crash.

Problem

The program crashes when handling a specific assembly. The crash cannot be reproduced with another assembly.

Solution

The issue is often caused by problematic part geometry or assembly constraints.
You can check the geometry of the parts using the Analyze function.
If the analysis reports that a part has invalid ACIS geometry, you should examine that part more closely and, if necessary, repair the faulty geometry. You can also try running a heal operation on the part.

If the crash or freeze occurs during part updates, it is often due to the constraint solver crashing or hanging.
This means there are faulty assembly constraints in the model, causing the program to crash when the model is updated.

If the problem occurs immediately after pressing F5 (i.e., when updating parts and solving constraints), you can try the following:

Change the value of the askupdate keyword from 0 to 1 (see step 2 in related instructions) so that automatic updates do not occur when opening the model.
Open the model.
Fix all parts in place.
Press F5.

If the program works normally this way, the problem is indeed in the constraint solver. Save the model and narrow down the problem as follows:

Detach parts/subassemblies (that were originally free) one by one, pressing F5 after each detachment.
Remove the problematic part, reinsert it, and reposition it.

Alternative approach:

After opening the model, select all constraints in the constraint tree and use the Exclude from Solve function.
Restore the constraints one by one with the Include in Solve function, and if the program does not crash/freeze, save the model.
Once you find the problematic constraint, delete it.