A simple PowerShell class which converts HRESULT into a human-friendly error

Get-ActualError.ps1

class ActualError {
    [int]$HResult;
    [string]$HResultHex;
    [string]$HResultBin;
    [string]$Facility;
    [int]$FacilityCode;
    [int]$ErrorCode;
    [bool]$IsFailure;
    [string]$Message;
    [bool]$IsCustom;
    [bool]$IsServerFailure;
}

function Get-ActualError
{
    param([int]$hresult)

    $actualError = [ActualError]::new();

    $actualError.HResult = $hresult;
    $actualError.HResultBin = [System.Convert]::ToString($hresult,2).PadLeft(32,'0');
    $actualError.HResultHex = "0x" + $hresult.ToString("X2");
    $actualError.Message = (New-Object System.ComponentModel.Win32Exception($hresult)).Message;

    $actualError.ErrorCode = $hresult -band 0xFFFF;

    $hresult = $hresult -shr 16;
    $actualError.FacilityCode = $hresult -band 0x7FF;
    
    $hresult = $hresult -shr 11;
    $hresult = $hresult -shr 1;    
    $hresult = $hresult -shr 1;
    $actualError.IsCustom = ($hresult -band 1) -eq 1;

    $hresult = $hresult -shr 1;
    $actualError.IsServerFailure = ($hresult -band 1) -eq 1;

    $hresult = $hresult -shr 1;
    $actualError.IsFailure = ($hresult -band 1) -eq 1;
    
    $actualError.Facility = switch ($actualError.FacilityCode)
    {
        0 { 'FACILITY_NULL'; }
        1 { 'FACILITY_RPC'; }
        2 { 'FACILITY_DISPATCH'; }
        3 { 'FACILITY_STORAGE'; }
        4 { 'FACILITY_ITF'; }
        7 { 'FACILITY_WIN32'; }
        8 { 'FACILITY_WINDOWS'; }
        9 { 'FACILITY_SECURITY'; }
        9 { 'FACILITY_SSPI'; }
        10 { 'FACILITY_CONTROL'; }
        11 { 'FACILITY_CERT'; }
        12 { 'FACILITY_INTERNET'; }
        13 { 'FACILITY_MEDIASERVER'; }
        14 { 'FACILITY_MSMQ'; }
        15 { 'FACILITY_SETUPAPI'; }
        16 { 'FACILITY_SCARD'; }
        17 { 'FACILITY_COMPLUS'; }
        18 { 'FACILITY_AAF'; }
        19 { 'FACILITY_URT'; }
        20 { 'FACILITY_ACS'; }
        21 { 'FACILITY_DPLAY'; }
        22 { 'FACILITY_UMI'; }
        23 { 'FACILITY_SXS'; }
        24 { 'FACILITY_WINDOWS_CE'; }
        25 { 'FACILITY_HTTP'; }
        26 { 'FACILITY_USERMODE_COMMONLOG'; }
        27 { 'FACILITY_WER'; }
        31 { 'FACILITY_USERMODE_FILTER_MANAGER'; }
        32 { 'FACILITY_BACKGROUNDCOPY'; }
        33 { 'FACILITY_CONFIGURATION'; }
        33 { 'FACILITY_WIA'; }
        34 { 'FACILITY_STATE_MANAGEMENT'; }
        35 { 'FACILITY_METADIRECTORY'; }
        36 { 'FACILITY_WINDOWSUPDATE'; }
        37 { 'FACILITY_DIRECTORYSERVICE'; }
        38 { 'FACILITY_GRAPHICS'; }
        39 { 'FACILITY_NAP'; }
        39 { 'FACILITY_SHELL'; }
        40 { 'FACILITY_TPM_SERVICES'; }
        41 { 'FACILITY_TPM_SOFTWARE'; }
        42 { 'FACILITY_UI'; }
        43 { 'FACILITY_XAML'; }
        44 { 'FACILITY_ACTION_QUEUE'; }
        48 { 'FACILITY_PLA'; }
        48 { 'FACILITY_WINDOWS_SETUP'; }
        49 { 'FACILITY_FVE'; }
        50 { 'FACILITY_FWP'; }
        51 { 'FACILITY_WINRM'; }
        52 { 'FACILITY_NDIS'; }
        53 { 'FACILITY_USERMODE_HYPERVISOR'; }
        54 { 'FACILITY_CMI'; }
        55 { 'FACILITY_USERMODE_VIRTUALIZATION'; }
        56 { 'FACILITY_USERMODE_VOLMGR'; }
        57 { 'FACILITY_BCD'; }
        58 { 'FACILITY_USERMODE_VHD'; }
        60 { 'FACILITY_SDIAG'; }
        61 { 'FACILITY_WEBSERVICES'; }
        61 { 'FACILITY_WINPE'; }
        62 { 'FACILITY_WPN'; }
        63 { 'FACILITY_WINDOWS_STORE'; }
        64 { 'FACILITY_INPUT'; }
        66 { 'FACILITY_EAP'; }
        80 { 'FACILITY_WINDOWS_DEFENDER'; }
        81 { 'FACILITY_OPC'; }
        82 { 'FACILITY_XPS'; }
        83 { 'FACILITY_RAS'; }
        84 { 'FACILITY_MBN'; }
        84 { 'FACILITY_POWERSHELL'; }
        85 { 'FACILITY_EAS'; }
        98 { 'FACILITY_P2P_INT'; }
        99 { 'FACILITY_P2P'; }
        100 { 'FACILITY_DAF'; }
        101 { 'FACILITY_BLUETOOTH_ATT'; }
        102 { 'FACILITY_AUDIO'; }
        109 { 'FACILITY_VISUALCPP'; }
        112 { 'FACILITY_SCRIPT'; }
        113 { 'FACILITY_PARSE'; }
        120 { 'FACILITY_BLB'; }
        121 { 'FACILITY_BLB_CLI'; }
        122 { 'FACILITY_WSBAPP'; }
        128 { 'FACILITY_BLBUI'; }
        129 { 'FACILITY_USN'; }
        130 { 'FACILITY_USERMODE_VOLSNAP'; }
        131 { 'FACILITY_TIERING'; }
        133 { 'FACILITY_WSB_ONLINE'; }
        134 { 'FACILITY_ONLINE_ID'; }
        153 { 'FACILITY_DLS'; }
        160 { 'FACILITY_SOS'; }
        176 { 'FACILITY_DEBUGGERS'; }
        231 { 'FACILITY_USERMODE_SPACES'; }
        256 { 'FACILITY_DMSERVER'; }
        256 { 'FACILITY_RESTORE'; }
        256 { 'FACILITY_SPP'; }
        257 { 'FACILITY_DEPLOYMENT_SERVICES_SERVER'; }
        258 { 'FACILITY_DEPLOYMENT_SERVICES_IMAGING'; }
        259 { 'FACILITY_DEPLOYMENT_SERVICES_MANAGEMENT'; }
        260 { 'FACILITY_DEPLOYMENT_SERVICES_UTIL'; }
        261 { 'FACILITY_DEPLOYMENT_SERVICES_BINLSVC'; }
        263 { 'FACILITY_DEPLOYMENT_SERVICES_PXE'; }
        264 { 'FACILITY_DEPLOYMENT_SERVICES_TFTP'; }
        272 { 'FACILITY_DEPLOYMENT_SERVICES_TRANSPORT_MANAGEMENT'; }
        278 { 'FACILITY_DEPLOYMENT_SERVICES_DRIVER_PROVISIONING'; }
        289 { 'FACILITY_DEPLOYMENT_SERVICES_MULTICAST_SERVER'; }
        290 { 'FACILITY_DEPLOYMENT_SERVICES_MULTICAST_CLIENT'; }
        293 { 'FACILITY_DEPLOYMENT_SERVICES_CONTENT_PROVIDER'; }
        305 { 'FACILITY_LINGUISTIC_SERVICES'; }
        885 { 'FACILITY_WEB'; }
        886 { 'FACILITY_WEB_SOCKET'; }
        1094 { 'FACILITY_AUDIOSTREAMING'; }
        1536 { 'FACILITY_ACCELERATOR'; }
        1793 { 'FACILITY_MOBILE'; }
        1996 { 'FACILITY_WMAAECMA'; }
        2049 { 'FACILITY_WEP'; }
        2050 { 'FACILITY_SYNCENGINE'; }
        2168 { 'FACILITY_DIRECTMUSIC'; }
        2169 { 'FACILITY_DIRECT3D10'; }
        2170 { 'FACILITY_DXGI'; }
        2171 { 'FACILITY_DXGI_DDI'; }
        2172 { 'FACILITY_DIRECT3D11'; }
        2184 { 'FACILITY_LEAP'; }
        2185 { 'FACILITY_AUDCLNT'; }
        2200 { 'FACILITY_WINCODEC_DWRITE_DWM'; }
        2201 { 'FACILITY_DIRECT2D'; }
        2304 { 'FACILITY_DEFRAG'; }
        2305 { 'FACILITY_USERMODE_SDBUS'; }
        2306 { 'FACILITY_JSCRIPT'; }
        2561 { 'FACILITY_PIDGENX'; }   
    }

    return $actualError;
}

Usage:
Get-ActualError 0x800706BA

Result:
HResult : -2147023174
HResultHex : 0x800706BA
HResultBin : 10000000000001110000011010111010
Facility : FACILITY_WIN32
FacilityCode : 7
ErrorCode : 1722
IsFailure : True
Message : RPC server is unavailable
IsCustom : False
IsServerFailure : False