The log from 2015 when it fails to install:
[1A74:1A48][2019-09-20T16:28:15]i001: Burn v3.7.3813.0, Windows v6.1 (Build 7601: Service Pack 1), path: C:\Users\Douglas\Desktop\15vc_redist.x86.exe, cmdline: '-burn.unelevated BurnPipe.{9FA34F94-0AA8-4E9F-89F6-8A0BC06A304F} {C0983830-0624-407E-B066-DB8984440B1B} 4196'
[1A74:1A48][2019-09-20T16:28:15]i000: Setting string variable 'WixBundleLog' to value 'C:\Users\Douglas\AppData\Local\Temp\dd_vcredist_x86_20190920162815.log'
[1A74:1A48][2019-09-20T16:28:15]i000: Setting string variable 'WixBundleOriginalSource' to value 'C:\Users\Douglas\Desktop\15vc_redist.x86.exe'
[1A74:1A48][2019-09-20T16:28:15]i000: Setting string variable 'WixBundleOriginalSourceFolder' to value 'C:\Users\Douglas\Desktop\'
[1A74:1A48][2019-09-20T16:28:15]i000: Setting string variable 'WixBundleName' to value 'Microsoft Visual C++ 2015 Redistributable (x86) - 14.0.23026'
[1A74:1A48][2019-09-20T16:28:15]i100: Detect begin, 10 packages
[1A74:1A48][2019-09-20T16:28:15]i000: Setting version variable 'windows_uCRT_DetectKey' to value '10.0.10240.16390'
[1A74:1A48][2019-09-20T16:28:15]i000: Setting numeric variable 'windows_uCRT_DetectKeyExists' to value 1
[1A74:1A48][2019-09-20T16:28:15]i102: Detected related bundle: {67f67547-9693-4937-aa13-56e296bd40f6}, type: Upgrade, scope: PerMachine, version: 14.16.27012.6, operation: Downgrade
[1A74:1A48][2019-09-20T16:28:15]i108: Detected compatible package: vcRuntimeMinimum_x86, provider: Microsoft.VS.VC_RuntimeMinimumVSU_x86,v14, installed: {7B77DE7F-5219-435E-9CE1-FC77F1D4CCAD}, version: 14.16.27012, chained: {A2563E55-3BEC-3828-8D67-E5E8B9E8B675}
[1A74:1A48][2019-09-20T16:28:15]i103: Detected related package: {7B77DE7F-5219-435E-9CE1-FC77F1D4CCAD}, scope: PerMachine, version: 14.16.27012.0, language: 0 operation: Downgrade
[1A74:1A48][2019-09-20T16:28:15]i108: Detected compatible package: vcRuntimeAdditional_x86, provider: Microsoft.VS.VC_RuntimeAdditionalVSU_x86,v14, installed: {DD6BC8D7-4582-4677-BAAC-4AB933E6C315}, version: 14.16.27012, chained: {BE960C1C-7BAD-3DE6-8B1A-2616FE532845}
[1A74:1A48][2019-09-20T16:28:15]i103: Detected related package: {DD6BC8D7-4582-4677-BAAC-4AB933E6C315}, scope: PerMachine, version: 14.16.27012.0, language: 0 operation: Downgrade
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i052: Condition '(windows_uCRT_DetectKeyExists AND windows_uCRT_DetectKey >= v10.0.10137.0)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: vcRuntimeMinimum_x86, state: Obsolete, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: vcRuntimeAdditional_x86, state: Obsolete, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: Windows81_x86, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: Windows81_x64, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: Windows8_x86, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: Windows8_x64, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: Windows7_MSU_x86, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: Windows7_MSU_x64, state: Present, cached: Complete
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: WindowsVista_MSU_x86, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i101: Detected package: WindowsVista_MSU_x64, state: Present, cached: None
[1A74:1A48][2019-09-20T16:28:15]i052: Condition 'VersionNT >= v6.0 OR (VersionNT = v5.1 AND ServicePackLevel >= 2) OR (VersionNT = v5.2 AND ServicePackLevel >= 1)' evaluates to true.
[1A74:1A48][2019-09-20T16:28:15]i199: Detect complete, result: 0x0
[1A74:1718][2019-09-20T16:28:19]e000: Error 0x80070666: Cannot install a product when a newer version is installed.
I've got "...2017 Redistributable...", two instances of them but here's the log.
Doug