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How to install BestSync?

How to uninstall BestSync?

Question about licence and activation.

Question about FTP synchronisation.

Report Error to RiseFly Software.

How do I use BestSync for data backup?

>>Tutorial for sync with FTP server

>>Tutorial for sync with network folder

>>Tutorial for downloading huge files from web server

BestSync integrates a backup mechanism. All the files changed or deleted at the synchronising time are backed up. BestSync can also backup a full version of your data. BestSync maintains the history versions. You can restore the files from the history versions and compare the difference between the files.
Just select the " Backup changed files when synchronisation (deleted or replaced)" option in the "Backup" wizard page.

Does BestSync lost file or damage file during synchronising?

No, BestSync uses a intermediate file in target folder during copy file. Only when the file is copied successfully, the intermediate is renamed to the target file. BestSync's backup mechanism ensures all the files changed or deleted during synchronising time are backed up. 

Can BestSync synchronise the opened or locked files, such as data base file?

Yes, BestSync supports " Volume Shadow Copy Service " of Windows Server 2012/2016/2019/2022, Windows 8/10/11, even opened files or locked files such as SQL data base file, OS registry file, Outlook PST files can be synchronised/backed up correctly. Other software may fail if the files are using. You need not worry this if you are using BestSync.
Just select the " Use ""Volume Shadow Copy Service" to copy opened files,..." option in the "Volume Shadow Copy" wizard page. If you are using 32Bit OS, please download the use "SetupBestSync.exe /BIT=32" command line to install the 32Bit version of BestSync.

Why did I fail to backup the opened/locked file?

BestSync can backup opened/locked files. if you failed to do it, please check following points:

1. For backup the opened files such as outlook .pst file, you must check "Use 'Volume Shadow Copy Service' to copy opened files..." option in the "Volume Shadow Copy" wizard page. Please note the 'Volume Shadow Copy Service' option can only be used under Windows Server 2012/2016/2019/2022, Windows 8/10/11.

2. If you checked the "Use 'Volume Shadow Copy Service'..." option, but still can not copy the opened files, please check if the VSS functions correctly. You can confirm BestSync's log file to check if BestSync failed to create the VSS. The log file is in following location:

If your OS is Windows XP, the log file is:

[OS Drive] :\Documents and Settings\All Users\Application Data\RiseFly\BestSync 20XX\service.log

If your OS is Windows VISTA, the log file is:

[OS Drive] :\ProgramData\RiseFly\BestSync 20XX\service.log

3. If you find that BestSync failed to create the VSS, please check if the VSS is installed correctly in the OS. Follow following steps to check the VSS state:

  • (1). Open the "Control Panel".
  • (2). Click the "Performance and Maintenance".
  • (3). Click the "Administrative Tools".
  • (4). Double-click the "Services".
  • (5). Please confirm if the "Volume Shadow Copy" service is in the list.

4. If you find that the "Volume Shadow Copy" service is not in the list. Please download it from following URL and install it:

After the service is installed, please try to start it by double-click on it and press the "start" button to see if the service can be started correctly.

How to setup the task to run as a Windows Service?

1. If the task is set to synchronise with a network drive, please check this point first.

2. Set the task to run as a Windows Service in the schedule.

Run as service

If the task is not running as a Windows Service, please check following points:

1. Open the service manager of the "Control Panel" to see if the "BestSync Service" is listed. The BestSync installer will install the service automatically when it is installed. 
If "BestSync Service" is not in the service list, you can install the service manually by following command line:
<X:\Program Files\RiseFly\BestSync 2023 >\BestSyncSvc.exe /install

If the "BestSync Service" has not started, start the service in the Service Manager. (BestSync will start the service automatically when you set the task as a Windows Service.)

 2. Please note to run the task as a Windows Service, you need the Business Licence.

How can I avoid "No more connections can be made to this remote computer because there are already as many connections as the computer can accept." error? or

How can I avoid the "Drive is not ready" error when synchronise with a net folder as windows service?

When the task synchronises with a network drive (folder), and is set to run as Windows Service, after the task runs for a period, the task end with "Drive not ready" error. In the "Option"/"View Log File" dialogbox, there is an error string "No more connections can be made to this remote computer because there are already as many connections as the computer can accept."

The cause of this problem:
Windows 7/8/10 only allow maximum 10 sessions for sharing folders over network at the same time. And when tasks are running as Windows Service, each thread uses one session. For avoiding this problem, please try the following settings.

1. If all the tasks can run under a same local user account, please try the following steps:

(1)Press "WIN+R" hot key, run "services.msc" to start "Services" manager:

start servic manager

(2)Setup the logon account of BestSync Service:

Select "BestSync Service" in the service list:


Start "Services" Program

Double click "BestSync Service" to show the property:

service logon

Setup a local account that BestSync Service will run under it.

(3)In the "Browse Folder" dialog-box, leave "Local User" and "Password" be empty in the "Impersonate a local user when run as windows service" setting group.

net logon

This will let BestSync Service to use the account set in the property of the service. In this way, all the threads that logon to a same net folder will use only one session.

2. If the tasks must run under different local user account, please do not use "Process multiple files simultaneously" option in "Copy Options" of the task setting.

How to force BestSync copy NTFS permissions?

There is a "Copy NTFS permissions" option in "Copy Options" setting TAB, please check this option.
Because the above option needs the administrator privilege, please also start BestSync by the administrator priority.
You can run BestSync as administrator automatically by check the following global option:
Click "Option"/"Option" menu.
Check "Start BestSyunc when windows starts", "Run as administrator" option in the "General" setting tab.
At the first time, please exit BestSync, then start BestSync by "Run as administrator" context menu.

Is there a limitation on the number or the size of file that BestSync can process?

For the file number, BestSync is designed to use smallest memory to analyze the file change. We have tested BestSync 32 Bit version on the system that has 2G memory, BestSync can synchronise folder that has 3,000,000 more files. We recommend you to use the 64 bit version of BestSync if you need to synchronise folders that has more than 3,000,000 files.
For the file size, BestSync uses 64-bit integer to record file size, almost all the file in the real world can be processed.

How does BestSync determine whether a file has been changed?

Here are the basic principles of BestSync's synchronisation algorithm:

  • The main algorithm of BestSync to detect file change and deletion .
  • Implements 1-directional or true bi-directional synchronisation.
  • Uses windows shell APIs routines only. No system injection, hooks, drivers or other tricks.
  • File and folder metadata for each synchronisation session is collected and stored in a database.
  • Recent changes are detected from file timestamps and last collected data.
  • Timestamp comparing rule:
    1. When sync between FAT and NTFS, if the difference of the file timestamp is less than 3 seconds, the file is see as the same.
    2. When sync between local and FTP server, time stamps are converted to UTC time, and if the difference of the file timestamp is less than 60 seconds, the file is see as the same.
  • Changed or deleted files are backed up by option.
  • No extra data files are generated in the sync folders.
  • One-thread for one task for better performance.

How does the application handle deleted files and folders?

BestSync recognizes that you have added or deleted a file or a folder from one location,  and adds or deletes it from the other (by option). 

Why does my spyware guard application claim that BestSync may contain spyware?

This is because BestSync checks for software updates automatically. No personal information is sent over the internet. This function can be switched off in the option dialog box.

What type of files can be synchronised?

BestSync is designed to synchronise and backup personal data or enterprise data.
For instance, MS Office documents, pictures, mailbox  files, web contents or any other files. Data replication between computers or removable media allows you to use and modify them when you want and where you want: at home, in the office, on a business trip and so on. Furthermore, you get data backup with no additional effort.

Synchronization of system folders are very simple, only a one click selection in the folder list. For example, "My documents", "My Pictures", "Outlook Express" mailbox, "My favorites", "CD Burning" etc.

How does BestSync synchronise two computers by an USB drive?

You can use virtually any removable device to synchronise your data between computers:

  • USB Drive
  • Removable Hard Drive
  • Zip Drive
  • Floppy Disk
  • Flash Memory Card
  • MP3 Player
  • Digital Camera

BestSync can compress and encrypt file to the removable media, and decompress and decrypt the file from the removable media. BestSync protects you data even though you lost it.
BestSync handles the insertion trigger event to sync the files with the removable media automatically, when the task ends, just take out the drive directly, because BestSync flush the drive to ensure all the files have written out.

Why does the system sometimes assign a different drive letter to my USB devices? How do I set up BestSync to synchronise with a specific device?

BestSync identifies a removable drive by the volume label, serial number of the drive.
If the USB device is mounted to a different drive letter, or a different USB device is mounted to the same drive letter, BestSync will not act by mistake.

To assign the USB device to the same drive letter, Go to Control Panel/Administrative Tools/Computer Management. Select Disk Management. Click the right mouse button on the drive. Select "Change the Drive Letter and Paths..." for the drive and then assign the letter you want to the drive letter you specified.

How do I synchronise Outlook email and contact etc between my laptop and desktop PCS.

Before setup synchronisation tasks in BestSync, please setup the same email accounts in Outlook of both laptop and desktop PC, and ensure that Outlook can send and receive email. Then setup two synchronisation tasks, one in the laptop, and the other in the desktop:
1. On your laptop, create a task profile like this:
Folder1: In the "General" wizard Page, Select "Outlook" in the combo box, Folder1 is set to "Outlook|\" automatically.
Folder2: Set to a shared folder or a folder in USB drive.
2. On your desktop PC, create a task profile like this:
Folder1: In the "General" wizard Page, Select "Outlook" in the combo box, Folder1 is set to "Outlook|\" automatically.
Folder2: Set to the same folder as the task in laptop.

Please note that 32bit BestSync can only sync with 32bit Outlook, and 64 bit BestSync can only sync with 64bit Outlook. 

How to run Sync-tasks when Windows log off or shutdown?

What should I do if I haven't found an answer to my question here?

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