How do I configure proftpd to allow transfer resumption (for downloads and uploads)?
To allow downloads to be resumed, you need to use the AllowRetrieveRestart configuration directive. To allow uploads to be resumed, you need to use both the AllowOverwrite and AllowStoreRestart directives. The reason that both need to be allowed is that a restarted/resumed upload is a form of overwriting the file. Also note that using HiddenStores and AllowStoreRestart is incompatible, as mentioned in the documentation for the AllowStoreRestart and HiddenStores directives.
