I have created the below document long long time ago for my own reference, please read it and I'm sure it will help you solving the problem, u will need to change the registry keys and paths to the correct ones
Offline Definition: -
Offline mode means that there’s a network or server failure preventing a POS machine from connecting to the store database and therefore the POS machine connects to a local database that has the necessary information to post transactions, this local database is called the offline database and it’s being synchronized every time a Z report is generated.
How a POS machine goes offline: -
While a POS machine is working in normal mode (on the main database on the server), a server or network failure might occur. In that case, the POS application will generate a run time error and the application will exit unexpectedly. When the cashier tries to re-open the POS application, the following scenario will be applied: -
1. The POS application will try to connect to the server main database within the pre-configured ‘Connect Timeout’ in the Store Operations Administrator (which is 15 seconds in our implementation)
2. The application will then try to connect to the pre-defined offline database (which is usually stored locally in our implementation though it might not) within the pre-defined ‘Connect Timeout’ for the offline database in the Store Operations Administrator.
3. The POS application will supposedly succeed in connecting to the offline database (if it’s properly configured).
4. The POS application will display a message telling that it’s working in offline mode and will change the “TerminalOffline” flag in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Retail Management System\Store Operations\POS User\ from ‘False’ to ‘True’ stating that the application is working offline.
5. The POS application will keep working offline and will not sense by itself that the network or the server comes up.
6. Any POS user who has the right to exit the application should close the POS application and re-open it.
7. The POS application will check the main database (it does this every time u open it) and will be able to connect to it since the network and the server are up
8. The POS application will check the “TerminalOffline” flag too to know if there are some transactions to upload or not.
9. The POS application will find the “TerminalOffline” flag set to ‘True’ and therefore will display a message stating that the main database in back online and will ask about restoring the offline transactions to the main database.
10. If the cashier presses ‘No’, nothing new will happen and the POS application will continue working offline.
11. If the cashier presses ‘Yes’, the POS application will upload the offline transactions to the main database (if any kind of failure in server or network occurs while uploading transactions, the application will upload the uploaded transactions again resulting in transactions’ duplication).
12. After the POS application uploads ALL the transactions, it will change the “TerminalOffline” flag in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Retail Management System\Store Operations\POS User\ from ‘True’ to ‘False’ stating that the application is not working offline anymore.
13. The POS application is working now online and all the offline transactions have been uploaded to the server just waiting for the blind closed batches to be closed.
What happens if the POS machine goes offline without having access to edit the registry?
This typically happen when the user is a normal user
1. The POS application will try to connect to the server main database within the pre-configured ‘Connect Timeout’ in the Store Operations Administrator (which is 15 seconds in our implementation)
2. The application will then try to connect to the pre-defined offline database (which is usually stored locally in our implementation though it might not) within the pre-defined ‘Connect Timeout’ for the offline database in the Store Operations Administrator.
3. The POS application will supposedly succeed in connecting to the offline database (if it’s properly configured).
4. The POS application will display a message telling that it’s working in offline mode and will TRY to change the “TerminalOffline” flag in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Retail Management System\Store Operations\POS User\ from ‘False’ to ‘True’ but unfortunately will fail in changing this registry value (BUG).
5. Instead of informing the user about failure in changing the registry value, the POS application will work offline without changing the registry value that’s a must to know its status and therefore resulting in unexpected behavior afterwards.
6. The POS application will record its transactions locally in the offline database while working offline although the registry value “TerminalOffline” is still ‘False’.
7. When the network and server are back up. Any POS user who has the right to exit the application will close the POS application and re-open it.
8. The POS application will check the main database (it does this every time u open it) and will be able to connect to it since the network and the server are up
14. The POS application will check the “TerminalOffline” flag too to know if there are some transactions to upload or not.
9. The POS application will find the “TerminalOffline” flag set to ‘False’ (this shouldn’t happen) and therefore will do nothing except working normally in online mode as if it was never in offline mode (the POS application doesn’t know in this case that it was in offline mode).
10. The offline transactions will not be uploaded to the main database and there will be no blind closed batches.
How to resolve a POS machine going offline then back online without sending its sales to the main database?
1. Exit the POS application
2. Logoff windows and logon as Administrator or any other user who has access to edit the registry.
3. If the application opens by itself (in the startup for example), close it.
4. Open the registry (regedit.exe).
5. Change “TerminalOffline” flag in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Retail Management System\Store Operations\POS User\ from ‘False’ to ‘True’
6. Verify the records to be uploaded in the [Transaction] table using ‘SELECT’ statement affecting the offline database.
7. State the Register number from the registry from HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Retail Management System\Store Operations\POS User\Register\Number
8. Run an ‘UPDATE’ statement on the Register.CurrentBatchNumber to change the value of this field for the intended register only in the offline database and make its new value the same as the BatchNumber previously selected in the pre-executed ‘SELECT’ statement (Only 1 row will be affected).
9. Open the POS application, it will display a message stating that the main database in back online and will ask about restoring the offline transactions to the main database.
10. Press ‘Yes’
11. The offline transactions will be uploaded to the main database.
12. Exit the POS application.
13. Logoff Windows and logon using the normal Windows account.
14. Make sure to give the intended Windows account the proper privileges to edit the “Sales Management Systems” key in the registry using Group Policy or even Local Security Policy.
