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Timestamps
Particularly when you want to use some of the synchronization features, first make sure that WinSCP will be able to convert timestamps from local conventions to remote server conventions and vice versa.
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Conversion
There are several factors that affect conversion and interpretation of the timestamps:
| Factor | Symptom |
|---|---|
| Daylight saving time (DST) | Timestamps of some files are shifted by one hour. |
| Server timezone offset | Timestamps of all files are shifted by the same time span. SCP and FTP protocols are affected. |
| Local file system is FAT | File timestamp is always rounded to the next even second. This is property of old FAT filesystem. For this reason WinSCP ignores less than 2-seconds time difference with all its synchronization features. Note that FAT is used rarely nowadays, mostly with removable medias only. |
| Timestamp precision | Files changed shortly after previous synchronization are not synchronized. SCP and FTP protocols are affected. |
Also note that for WinSCP to try to convert file timestamp at all, you need to have transfer option Preserve timestamp enabled.
Windows vs. Unix
For certain reasons certain versions of Microsoft Windows (NT, 2000, XP, 2003 and Vista) shifts timestamps of ALL files by one hour once Daylight Saving Time starts and/or finishes1. For example, for file created on 2005-02-25 14:00, Windows applications (like Windows Explorer or WinSCP) will show modification time 2005-02-25 15:00, when DST is in effect. Unfortunately, to allow synchronization functions to work, WinSCP has to apply the same correction to timestamps of remote files as Windows apply to timestamps of local files. As the remote operating system, being typically Unix-style, usually does not perform the Windows NT-style correction, you will see by default different timestamps in directory listing of WinSCP, than you see in directory listing on the server (for example in ls listing). You can change this in session preferences, but that will render synchronization non-functional.
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Synchronization
If you happen to have the same files locally and remotely with the different timestamps, you can update them without transferring the files again. Use function Synchronize in Synchronize timestamps mode.
- See article Beating the Daylight Savings Time bugBack