The 'fatal: the remote end hung up unexpectedly' error often results from network interruptions, large file sizes, or buffer limitations during push or clone operations. If dealing with large files, consider using Git Large File Storage (LFS) to track these files separately. Alternatively, increase Git’s buffer size by running `git config http.postBuffer 524288000`, which sets the buffer limit to 500MB, potentially resolving issues with large pushes. This command is particularly helpful when pushing large commits over slower networks, which may otherwise lead to timeouts or disconnections. Additionally, confirm you have a stable internet connection, as network instability can trigger this error. Try performing the action during off-peak hours or from a different network to reduce the chances of connection issues.