Fix:
The repo is private or the file is missing.
Log in to Hugging Face with huggingface-cli login and set your token.
Or, use "t5-small" or "t5-base"—official repos, which are public and have the config file.
Example:
from transformers import AutoTokenizer
tokenizer = AutoTokenizer.from_pretrained(“t5-base”)
Solution provided by Triskel Data Deterministic AI.