Duplicating a large remote export can consume local disk space and network traffic even when both the source and destination are remote folders. Check the route before starting, especially on a laptop with limited free space or a metered connection.

Write down the source server, account and path, then the intended destination. Decide whether you need a second independent file or simply another reference to the same working object. This guide concerns making a copy; it is not a request to move or delete the source.

Read the Duplicate dialog's actual route

In WinSCP's remote file panel, select the intended item and choose Files, Duplicate. Inspect Target session and Target remote path. A familiar folder name is not enough when several server sessions are open.

Within the same session, WinSCP offers direct duplication or a local temporary copy, subject to protocol and server support. Its documentation identifies SFTP copy-file or copy-data extensions and FTP SITE COPY as relevant capabilities. They can be inspected on the Capabilities page of Server and protocol information.

Some SFTP direct-copy workflows use a separate shell session. Do not treat that as permission to obtain shell access on a restricted account. Use only the server capabilities and access arrangement approved for the task.

For duplication to a different session, WinSCP documents a local temporary copy as the available route. Plan local space and both network legs accordingly. Two tabs whose hostnames look similar do not establish a direct server-to-server transfer.

Verify the route with a small representative copy

Try a harmless sample in the intended destination and inspect the selected method before accepting it. Check the result's name and contents and confirm that the original still exists at the source path. A duplicate with an unexpected operation mask or destination is not the required copy.

If direct duplication is unavailable, decide whether the local route is acceptable before attempting the large file. Do not repeatedly invoke the same operation assuming a remote destination eliminates local resource requirements.

After the accepted transfer, verify the large copy using the receiving application's checks and an appropriate integrity comparison. Retain the source until that result is accepted. Record the method used so a later operator can estimate the real time, storage and connection requirements instead of assuming every remote copy stays on the server.

Sources: WinSCP documentation, WinSCP documentation.