If you are repairing a , you actually cannot use v186. The newer chipsets (Snapdragon 888 and 8 Gen 1) require the encryption keys found only in v6+.

Version 1.86 (v186) arrived as a silent but revolutionary update, primarily distributed through OnePlus’s internal service centers and later leaked to XDA Developers and Telegram communities. Unlike consumer-ready tools like the OnePlus Recovery Tool, MSMDownloadTool v186 operates at the boot ROM level, and this specific build introduced critical refinements.