Error 0x8004010f: Database Not Found - Fix Guide 2025

Event ID: 9519
Source: MSExchangeIS
Level: Error

Failed to mount database "Mailbox Database 01".
Error: MapiExceptionNotFound: Unable to mount database.
(hr=0x8004010f, ec=-2147221233)

Additional information: The database file could not be found at
the specified path: D:\ExchangeDBs\DB01\DB01.edb

# Get configured database path
$DB = Get-MailboxDatabase "Mailbox Database 01"
$ConfiguredPath = $DB.EdbFilePath.PathName
$ConfiguredLogPath = $DB.LogFolderPath.PathName

Write-Host "Exchange expects database at: $ConfiguredPath" -ForegroundColor Yellow
Write-Host "Exchange expects logs at: $ConfiguredLogPath" -ForegroundColor Yellow

# Check if files exist at configured paths
if (Test-Path $ConfiguredPath) {
    Write-Host "✓ Database file FOUND at configured path" -ForegroundColor Green
} else {
    Write-Host "✗ Database file NOT FOUND at configured path" -ForegroundColor Red
}

# Search for database file in common locations
$SearchPaths = @("D:\", "E:\", "C:\Program Files\Microsoft\Exchange Server\")
foreach ($Path in $SearchPaths) {
    $Found = Get-ChildItem -Path $Path -Filter "$SearchPaths) {
    $Found = Get-ChildItem -Path $Path -Filter "*.edb" -Recurse -ErrorAction SilentlyContinue |
        Where-Object { $_.Name -eq $DB.Name + "-ErrorAction SilentlyContinue |
        Where-Object { $_.Name -eq $DB.Name + ".edb" }
    if ($Found) {
        Write-Host "-Host "✓ Database found at: $($Found.FullName)" -ForegroundColor Green
    }
}

# Dismount the database first (required before path change)
Dismount-Database "Mailbox Database 01" -Confirm:$false

# Update database file path to actual location
# Replace with your actual path where the .edb file exists
Set-MailboxDatabase "Mailbox Database 01" \
    -EdbFilePath "E:\NewDB\DB01\DB01.edb"

# Update log folder path if logs were also moved
Set-MailboxDatabase "Mailbox Database 01" \
    -LogFolderPath "E:\NewDB\DB01"

# Verify new paths are set correctly
Get-MailboxDatabase "Mailbox Database 01" |
    Format-List Name, EdbFilePath, LogFolderPath

# Force AD replication to propagate path change
repadmin /syncall /AeD

# Wait 30 seconds for replication
Start-Sleep -Seconds 30

# Restart Exchange Information Store service to pick up new config
Restart-Service MSExchangeIS -Force

# Wait for service to initialize
Start-Sleep -Seconds 30

# Mount the database
Mount-Database "Mailbox Database 01"

# Verify mount succeeded
Get-MailboxDatabase "Mailbox Database 01" |
    Format-List Name, Mounted, Server, EdbFilePath

# 1. Verify database is mounted at new path
Get-MailboxDatabase "Mailbox Database 01" |
    Format-Table Name, Mounted, EdbFilePath, LogFolderPath -AutoSize

# 2. Confirm file system paths match configuration
$DB = Get-MailboxDatabase "Mailbox Database 01"
$EdbPath = $DB.EdbFilePath.PathName
$LogPath = $DB.LogFolderPath.PathName

Write-Host "Checking file existence..."
Test-Path $EdbPath  # Should return True
Get-ChildItem $LogPath -Filter "*.log"  # Should list log files

# 3. Test mailbox connectivity
Test-MAPIConnectivity -Database "Mailbox Database 01"

# 4. Check Event Viewer for mount success
Get-EventLog -LogName Application -Source "MSExchangeIS" -Newest 10 |
    Where-Object { $_.Message -like "*Mailbox Database 01*" } |
    Select-Object TimeGenerated, EntryType, Message

# 5. Verify users can access mailboxes
Get-Mailbox -Database "Mailbox Database 01" -ResultSize 5 |
    ForEach-Object { Test-Mailbox $_.Alias }

# Save as Validate-ExchangeDatabasePaths.ps1
# Run before SAN migrations or storage changes

$Databases = Get-MailboxDatabase -Server $env:COMPUTERNAME

foreach ($DB in $Databases) {
    $EdbPath = $DB.EdbFilePath.PathName
    $LogPath = $DB.LogFolderPath.PathName

    Write-Host "\n========================================" -ForegroundColor Cyan
    Write-Host "Database: $($DB.Name)" -ForegroundColor Cyan
    Write-Host "========================================" -ForegroundColor Cyan

    # Check .edb file
    if (Test-Path $EdbPath) {
        $FileInfo = Get-Item $EdbPath
        Write-Host "✓ EDB File Found: $EdbPath" -ForegroundColor Green
        Write-Host "  Size: $([math]::Round($FileInfo.Length / 1GB, 2)) GB"2)) GB" -ForegroundColor Gray
        Write-Host "  Last Modified: $($FileInfo.LastWriteTime)" -ForegroundColor Gray
    } else {
        Write-Host "✗ EDB File NOT FOUND: $EdbPath" -ForegroundColor Red
        Write-Host "  ACTION REQUIRED: Locate database or restore from backup" -ForegroundColor Yellow
    }

    # Check log files
    $LogFiles = Get-ChildItem $LogPath -Filter "*.log" -ErrorAction SilentlyContinue
    if ($LogFiles) {
        Write-Host "✓ Log Files Found: $($LogFiles.Count) files in $LogPath"$LogPath" -ForegroundColor Green
    } else {
        Write-Host "✗ No log files found in: $LogPath" -ForegroundColor Red
    }

    # Check mount status
    $Status = Get-MailboxDatabase $DB.Name | Select-Object -ExpandProperty Mounted
    if ($Status) {
        Write-Host "✓ Database is currently MOUNTED" -ForegroundColor Green
    } else {
        Write-Host "⚠ Database is currently DISMOUNTED" -ForegroundColor Yellow
    }
}

Write-Host "\n========================================" -ForegroundColor Cyan
Write-Host "Validation Complete" -ForegroundColor Cyan
Write-Host "========================================" -ForegroundColor Cyan