Source note · Web proxies and TLS inspection that break UC clients
Microsoft lists forcing protocol downgrade or failover between client apps and Microsoft 365, such as UDP to TCP or TLS 1.3 to TLS 1.2, as a network scenario known to cause connectivity issues.
Checked 2026-10-14
- Vendor
- Microsoft
- Product
- Microsoft 365
- Subsystem
- network connectivity
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-10-14
- Checked
- 2026-10-14
Sources
- Microsoft 365 network connectivity principles — Microsoft · tier 2 current vendor documentation · Additional network considerations, bullet 3
Cite this note
APA
WarmTransfer. (2026, October 14). Web proxies and TLS inspection that break UC clients: source note tls-inspection-uc-clients-m365-protocol-downgrade. WarmTransfer. https://warmtransfer.net/knowledge/claims/tls-inspection-uc-clients-m365-protocol-downgrade
BibTeX
@misc{warmtransfer-claim-tls-inspection-uc-clients-m365-protocol-downgrade,
title = {Web proxies and TLS inspection that break UC clients: source note tls-inspection-uc-clients-m365-protocol-downgrade},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/tls-inspection-uc-clients-m365-protocol-downgrade},
note = {Source note tls-inspection-uc-clients-m365-protocol-downgrade, checked 2026-10-14}
}