Limits folder's content


I have a folder with 1.412 items. When I try to get folder’s content I’m getting 500 error code. I have another folder with a few items and it is working properly.
Which is the limit for folder’s items? Any idea to work with such folder or I have to make subfolders?
FYI: My DF version is 1.9.0


Just to confirm by “1.412 items” you mean 1412 items?


Yes 1412 items.
I have checked all files and I see some files don´t have read permissions, could be this the real issue?