How can I fix synchronization errors between my head office and branch office in BUSY?

To fix synchronization errors between your head office and branch office in BUSY, you can follow these steps:
Firstly, Take a backup of both the head office and branch office data.
Secondly, it depends on the errors you are facing:
SQl server does not exist 
1. First will check whether the HO and BO are on same location or not .
2. Whether port for HO-BO that is 1433 is opened and configured for the same.
3. In BUSY, we have to match the HO and BO configuration should always match.
4. To match Ho-Bo configuration in BUSY, Click on Administration>Configuration>Features/Options>Enterprises option 
5. In branch we have option to read Ho configuration from there we can match the configuration
6. SQl server information mentioned in that option only should also match.
7. Click on check connection option for the same to check whether SQl SERVER mentioned i scoorect or not.
8. At last we can check the internet if there any issue in internet from any of the end i.e is HO or BO

Some times we also faces Run time errors like
RTE 91 : Set Regional Settings of the system
RTE 5 : Reindex the HO and BO for the same 
RTE 70 : Always Run BUSY On administration mode