# Get recent sync exception events
Get-WinEvent -FilterHashtable @{
    LogName = 'Application'
    Id = 1008
    ProviderName = 'MSExchange ActiveSync'
    StartTime = (Get-Date).AddDays(-1)
} | Select-Object TimeCreated, Message | Format-List

# Extract unique users affected
$events = Get-WinEvent -FilterHashtable @{
    LogName = 'Application'
    Id = 1008
    StartTime = (Get-Date).AddDays(-1)
} -ErrorAction SilentlyContinue

$events | ForEach-Object {
    if ($_.Message -match 'users+(S+@S+)') {
        $matches[1]
    }
} | Sort-Object -Unique | ForEach-Object {
    Write-Host "Affected User: $_"
}

# Get mobile device details for affected user
$user = "affected.user@contoso.com"

Get-MobileDeviceStatistics -Mailbox $user | Format-List DeviceId, DeviceType, DeviceOS, DeviceUserAgent, LastSyncAttemptTime, LastSuccessSync, Status, DeviceAccessState, DeviceAccessStateReason

# Check for devices with sync issues
Get-MobileDeviceStatistics -Mailbox $user | Where-Object {
    $_.Status -ne "DeviceOK" -or
    $_.LastSyncAttemptTime -ne $_.LastSuccessSync
} | Format-Table DeviceId, DeviceType, Status, LastSyncAttemptTime, LastSuccessSync -AutoSize

# Find ActiveSync log directory
$exchangeInstallPath = (Get-ItemProperty HKLM:\SOFTWARE\Microsoft\ExchangeServer\v15\Setup).MsiInstallPath
$easLogPath = Join-Path $exchangeInstallPath "Logging\HttpProxy\Eas"

Write-Host "ActiveSync logs location: $easLogPath"

# Search for errors related to specific user
$user = "affected.user"
$logFiles = Get-ChildItem $easLogPath -Filter "*.log" |
    Where-Object { $_.LastWriteTime -gt (Get-Date).AddDays(-1) }

foreach ($log in $logFiles) {
    Select-String -Path $log.FullName -Pattern $user -Context 0,2 |
    Select-Object -First 10
}

# Search for specific error patterns
Select-String -Path "$easLogPath\*.log" -Pattern "Exception|500|error" -Context 1,1 |
    Select-Object -First 20

# Run New-MailboxRepairRequest to detect corruption
$mailbox = "affected.user@contoso.com"

# Check for all corruption types
$repairRequest = New-MailboxRepairRequest -Mailbox $mailbox -CorruptionType ProvisionedFolder, SearchFolder, AggregateCounts, Folderview -DetectOnly

# Monitor repair request progress
Start-Sleep -Seconds 30
Get-MailboxRepairRequest -Mailbox $mailbox | Format-List

# Check mailbox folder statistics for anomalies
Get-MailboxFolderStatistics -Identity $mailbox |
    Where-Object { $_.ItemsInFolder -gt 10000 -or $_.FolderSize -gt "500MB" } |
    Format-Table FolderPath, ItemsInFolder, FolderSize -AutoSize

# Check Exchange server health
Get-ServerHealth | Where-Object { $_.AlertValue -ne "Healthy" } |
    Format-Table Server, Name, AlertValue, CurrentHealthSetState -AutoSize

# Check ActiveSync virtual directory health
Get-ActiveSyncVirtualDirectory | Format-List Server, InternalUrl, ExternalUrl, BasicAuthEnabled

# Test ActiveSync connectivity
Test-ActiveSyncConnectivity -ClientAccessServer (Get-ExchangeServer | Where-Object {$_.ServerRole -match "ClientAccess"}).Name |
    Format-Table Scenario, Result, Latency, Error -AutoSize

# Check for database mount issues
Get-MailboxDatabaseCopyStatus | Where-Object { $_.Status -ne "Mounted" -and $_.Status -ne "Healthy" } |
    Format-Table Name, Status, CopyQueueLength, ReplayQueueLength -AutoSize

# Export potentially problematic calendar items to PST for analysis
$mailbox = "affected.user@contoso.com"
$exportPath = "\\server\share\CalendarExport.pst"

# Export calendar folder
New-MailboxExportRequest -Mailbox $mailbox -IncludeFolders "#Calendar#" -FilePath $exportPath -Name "CalendarExport"

# Monitor export progress
Get-MailboxExportRequest -Name "CalendarExport" | Get-MailboxExportRequestStatistics

# After identifying corrupted items via MFCMapi or by date range,
# you can delete specific items using Search-Mailbox
Search-Mailbox -Identity $mailbox -SearchQuery "received:01/15/2024..01/16/2024 kind:meetings"15/2024..01/16/2024 kind:meetings" -DeleteContent -Force

# For corrupted calendar items with bad recurrence patterns
Get-CalendarDiagnosticLog -Identity $mailbox -Subject "Recurring Meeting Name" |
    Format-List Subject, StartTime, EndTime, CalendarLogTriggerAction, ItemClass

# For persistent sync state corruption, clear at the mailbox level
$user = "affected.user@contoso.com"

# Disable and re-enable ActiveSync for the user
Set-CASMailbox -Identity $user -ActiveSyncEnabled $false
Start-Sleep -Seconds 10
Set-CASMailbox -Identity $user -ActiveSyncEnabled $true

# Verify the change
Get-CASMailbox -Identity $user | Format-List ActiveSyncEnabled, ActiveSyncMailboxPolicy

# User should remove and re-add Exchange account on device
# This forces complete sync state rebuild

# Run comprehensive mailbox repair
$mailbox = "affected.user@contoso.com"

# Create repair request for all corruption types
$repairJob = New-MailboxRepairRequest -Mailbox $mailbox -CorruptionType ProvisionedFolder, SearchFolder, AggregateCounts, Folderview, MessageId, ReplState, RuleMessageClass, MessagePtagCn

Write-Host "Repair request created: $($repairJob.Identity)"

# Monitor repair progress (can take hours for large mailboxes)
do {
    Start-Sleep -Seconds 60
    $status = Get-MailboxRepairRequest -Mailbox $mailbox | Select-Object -Last 1
    Write-Host "Status: $($status.Status) - Progress: $($status.Progress)%"$status.Progress)%"
} while ($status.Status -eq "Queued" -or $status.Status -eq "InProgress")

Write-Host "Repair completed with status: $($status.Status)"

# Check repair results
Get-MailboxRepairRequest -Mailbox $mailbox | Format-List *

# Check current ActiveSync attachment limits
Get-ActiveSyncMailboxPolicy | Format-List Name, MaxAttachmentSize, AttachmentsEnabled

# Create or modify policy with appropriate limits
$policyName = "Standard ActiveSync Policy"

# Set maximum attachment size (e.g., 25MB)
Set-ActiveSyncMailboxPolicy -Identity $policyName -MaxAttachmentSize 25MB -AttachmentsEnabled $true

# For users with large attachment needs, create separate policy
New-ActiveSyncMailboxPolicy -Name "Large Attachment Policy" -MaxAttachmentSize 50MB -AttachmentsEnabled $true

# Assign policy to specific users
Set-CASMailbox -Identity "executive@contoso.com" -ActiveSyncMailboxPolicy "Large Attachment Policy"

# Identify oversized items in affected mailbox
$mailbox = "affected.user@contoso.com"
Get-MailboxFolderStatistics -Identity $mailbox -FolderScope Inbox |
    ForEach-Object {
        Get-MailboxFolder -Identity "$mailbox:$($_.FolderPath)"$_.FolderPath)" |
        Get-MailboxFolderStatistics -IncludeAnalysis |
        Where-Object { [int64]($_.TopSubjectSize -replace '[^d]','') -gt 26214400 }
    }

# Remove corrupted calendar items using calendar diagnostics
$mailbox = "affected.user@contoso.com"

# Get calendar processing settings
Get-CalendarProcessing -Identity $mailbox | Format-List

# Check for problematic recurring meetings
$diagnostics = Get-CalendarDiagnosticLog -Identity $mailbox -StartDate (Get-Date).AddDays(-30) -EndDate (Get-Date)
$diagnostics | Where-Object {
    $_.ItemClass -eq "IPM.Appointment" -and
    $_.CalendarLogTriggerAction -eq "Create"
} | Group-Object Subject | Where-Object { $_.Count -gt 10 } |
Format-Table Name, Count

# For Outlook Web App calendar issues
Get-MailboxCalendarFolder -Identity "$mailbox:\Calendar" | Format-List

# Reset calendar folder permissions if needed
Remove-MailboxFolderPermission -Identity "$mailbox:\Calendar" -User Default -Confirm:$false
Add-MailboxFolderPermission -Identity "$mailbox:\Calendar" -User Default -AccessRights AvailabilityOnly