When a BizTalk WCF-SAP adapter client is running BAPI transactions, and the WCF-SAP adapter throws exceptions, you notice that the adapter client eventually runs out of connections over time, and the following error message is generated:
SAP.Middleware.Connector.RfcResourceException: Unable to allocate client in pool [NAME=<NCoConnectionName> USER=<UserName> CLIENT=<ClientId> LANG=<LangName> ASHOST=<ASHOST> SYSNR=<SYSNRNum>] -- peak connections limit <MaxConnectionCount> exceeded
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
This problem is fixed in the following cumulative update for BizTalk Server:
Cumulative Update 3 for BizTalk Server 2020
For information about the service packs and cumulative update list for BizTalk Server, see the following article in the Microsoft Knowledge Base:
2555976 Service pack and cumulative update list for BizTalk Server
For more information about BizTalk Server hotfixes, see the following article in the Microsoft Knowledge Base:
2003097 Information about BizTalk hotfixes and Cumulative Update support
Third-party information disclaimer
The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.