https://help.tallysolutions.com/docs/ts9rel54/ts9/release_notes.htm

Release Notes for Tally.Server 9 Release 5.0

Tally.Server 9 Series A Release 5.0 is compatible only with Tally.ERP 9 Series A Release 5.0 . Lower versions of Tally.ERP 9 are not compatible.

‚óŹ When performing bulk writing operations in Tally.Server 9, Tally.ERP 9 performance was slow, resolved: When bulk write operations (like frequent sync., import, BRS) were running in Tally.Server 9, Tally.ERP 9 was performing slowly.

Now, Tally.Server 9 and Tally.ERP 9 can be used simultaneously when the BRS frequency is high.