Microsoft names the BlockNonAdminUserInstall policy (including the Intune 'Block non admin user install' setting) as the most likely cause of Teams VDI error 16389 (E_FAIL); when it applies, SlimCore registration aborts and the call falls back to non-optimized or, where available, WebRTC.
Checked 2026-10-02
- Vendor
- Microsoft
- Product
- Microsoft Teams
- Subsystem
- VDI 2.0 SlimCore MSIX deployment
- Deployment
- vdi
- Region
- not restricted
- Release range
- current as of 2026-10-02
- Checked
- 2026-10-02
Sources
- Troubleshooting the VDI 2.0 solution for Teams — Microsoft · tier 2 current vendor documentation · Section 'Error 16389', note and cause table (BlockNonAdminUserInstall: Very high)
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting softphones in Citrix and VMware virtual desktops: source note vdi-softphone-troubleshooting-teams-err-16389-blocknonadmin. WarmTransfer. https://warmtransfer.net/knowledge/claims/vdi-softphone-troubleshooting-teams-err-16389-blocknonadmin
BibTeX
@misc{warmtransfer-claim-vdi-softphone-troubleshooting-teams-err-16389-blocknonadmin,
title = {Troubleshooting softphones in Citrix and VMware virtual desktops: source note vdi-softphone-troubleshooting-teams-err-16389-blocknonadmin},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/vdi-softphone-troubleshooting-teams-err-16389-blocknonadmin},
note = {Source note vdi-softphone-troubleshooting-teams-err-16389-blocknonadmin, checked 2026-10-02}
}