I have a FAT32 external hard drive where I keep backups downloaded from webserver. I have a directory with 30 subdirectories. One of the subdirectories contains 21381 files and when I try to copy more files into this directory I get 0x80070052 error. However,it's possible to copy one more file in this directory (only one) if I make it's name shorter (8 characters instead of 22 as it's original name).

How do I solve this problem? Now I can not synchronize external hard disk files with server files which is very important for me.