Faezeh Ladani
Ansys Employee

Hi Giovanni,

The error code  - 1073741819 is a Windows error message, which might not have to do anything with your AEDT project. But if related to your project, try the followings: 
It can be a memory access violation. For some reason, AEDT could not access memory. Sometimes, it is out of memory for a large design, or user permissions.. Sometimes, it may even go down to hardware fail. 
Also, make sure the path of the project (consisting of the name of the design, project, and the nested folders you save the file in) is not very long and close to 256 char limits. From the picture, this doesn't look to be the reason, but keep that in mind. 
Make sure you run on a disk with enough space, and with all read/write permissions for the user,  and also empty up the Temp folder. 
Hope this helps. If the issue remians, you may search the error code on Microsoft forum or other platforms to investigate further. Also, check if it is happening only for this project, or happening in different AEDT/other projects as well.