On a site I have to upload 2000+ image files. I talked to support about whether they could unzip a large file after I uploaded it. They could of course. I had concerns as to whether it would be possibe to sychronize that many files after being unzipped. So I started manually uploading with the file manager in about 7MB zipped files and having file manager unzip them. After about 500 files and 400MB I started getting an error

A critical error has occurred.
Object reference not set to an instance of an object.

Any thoughts?

Thanks in advance

Peter