Usually HTTP ERROR 500 is a server error but can in rare case be a programming error.
Check your php.ini file:
php.ini file.
post_max_size = 10M and upload_max_filesize = 10M should be set to the same value and the size that you need to upload.
Your server memory setting can also effect this memory_limit = 64M
Set to what your needs are.
What did you Try? What did you Get? What did you Expect?
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