Check exchange version. The best method is to visit link below and download the health check script. Alternately, the next two commands may show (get-exchangeserver may sometimes show old version).
Get-Command Exsetup.exe | ForEach {$_.FileVersionInfo}
Get-ExchangeServer | Format-List Name,Edition,AdminDisplayVersion
https://docs.microsoft.com/en-us/exchange/new-features/build-numbers-and-release-dates?view=exchserver-2019

Get-Mailbox -Identity first.last | fl DisplayName, Name, PrimarySmtpAddress, ServerName, Database, LegacyExchangeDN, RecipientTypeDetails, RoleAssignmentPolicy, CustomAttribute10
Get-MailboxFolderStatistics -Identity first.last | ft name,foldersize,itemsinfolder -auto
Get-MailboxStatistics first.last | Select -Expand TotalItemSize
Get-InboxRule -Mailbox first.last | ft Enabled,Name -auto
Get-MailboxJunkEmailConfiguration -Identity first.last | fl Identity, Enabled, ContactsTrusted, TrustedSendersAndDomains, BlockedSendersAndDomainsGet-MailboxAutoReplyConfiguration first.last | fl AutoReplyState, ExternalMessage, InternalMessage
Get-MailboxPermission first.last | where { ($_.IsInherited -eq $False) -and -not ($_.User -like "NT AUTHORITY\SELF") } | fl Identity,User,AccessRights
Get-MailboxFolderPermission first.last | fl Identity,User,AccessRightsGet-ADPermission first.last | Where { ($_.IsInherited -eq $False) -and -not ($_.User -like "NT AUTHORITY\SELF") } | ft User, Properties, AccessRights -auto
Get-Recipient -Identity first.last | where {$_.RecipientType -eq 'MailContact'} | Select -Expand Name | Get-MailContact | fl DisplayName, PrimarySmtpAddress, Identity, LegacyExchangeDN



- Powershell (x86) 32bit - Get-Module "ActiveDirectory"


* Search share for a user *
Get-ChildItem -Path \\SERVER\USER06$ | Get-ChildItem | Where-Object {$_.Name -eq "first.last"};
or
$strDir = "\\server01\user01$";
$strUser = "first.last";
Get-ChildItem -Path $strDir | Get-ChildItem | Where-Object {$_.Name -eq $strUser};


* Check user information *
if(!(Get-Module "ActiveDirectory")){Import-Module ActiveDirectory}
Get-ADUser first.last -Properties * -Server SERVERDC01 | fl Name,DisplayName,telephoneNumber,EmployeeID,EmployeeType


* Set H: Path *
if(!(Get-Module "ActiveDirectory")){Import-Module ActiveDirectory}
Set-ADUser first.last -server SERVERDC01 -HomeDrive "H" -HomeDirectory \\SERVERFS01\first.last


* Compare Folders *
$fso = Get-ChildItem -path "C:\Program Files (x86)\Hewlett-Packard\HPCA\Agent"
$fsoBU = Get-ChildItem -path "\\%machine%\c$\Program Files (x86)\Hewlett-Packard\HPCA\Agent"
Compare-Object -ReferenceObject $fso -DifferenceObject $fsoBU


* Compare folders AND subfolders *
$fso = Get-ChildItem -Recurse -path "C:\Program Files (x86)\Hewlett-Packard\HPCA\Agent"
$fsoBU = Get-ChildItem -Recurse -path "\\%machine%\c$\Program Files (x86)\Hewlett-Packard\HPCA\Agent"
Compare-Object -ReferenceObject $fso -DifferenceObject $fsoBU



* Public Folders *
Get-PublicFolder -Identity \sub -Recurse -ResultSize 100 | fl Replicas,Identity
Get-PublicFolder -Identity \sub -Recurse -ResultSize 100 | Export-CSV "C:\Public.csv"
Get-PublicFolder -Identity \sub -getchildren
Get-PublicFolder -Identity "\sub\sub\folder" -getchildren
Get-PublicFolder -identity "\sub\sub\folder\etc" -recurse | fl *
http://technet.microsoft.com/en-us/library/cc788135(v=exchg.80).aspx

* Check Public Folder Permissions
Get-PublicFolderClientPermission -Identity "\sub\folder\etc" | fl
Get-PublicFolderClientPermission -Identity "\sub\folder\etc" -User first.last | Format-List




Set-ExecutionPolicy Unrestricted

* Connect to Exchange server**
powershell -noexit -command Set-ExecutionPolicy Unrestricted; $Session = New-PSSession -ConfigurationName Microsoft.Exchange -ConnectionUri "http://serverex01/PowerShell/" -Authentication Kerberos ; Import-PSSession $Session -AllowClobber ; Set-ADServerSettings -ViewEntireForest $true ; Set-ADServerSettings -PreferredServer serverdc01



* Move AD Account to different domain: *
Import-Module ActiveDirectory
Get-ADUser -Server "serverex01" -Identity "user.name" | Move-ADObject -Server "serverdc01" -TargetPath "OU=USERS,OU=PTGN,OU=CNO,DC=server01,DC=test,DC=com" -TargetServer "serverdc01"



* Get server Stats *
Get-MailboxDatabase -Server serverex01 | fl *



* Get email statistics *
Get-Mailbox -Identity first.last
Get-MailboxStatistics -Identity "first.last" | Format-List
Get-Mailbox -Identity "first.last" | fl EmailAddressPolicyEnabled, EmailAddresses



* Check if Out OF Office reply is turned on (AutoReplyState) *
Get-MailboxAutoReplyConfiguration -Identity "first.last"



* Disable Out Of Office *
Set-MailboxAutoReplyConfiguration -Identity "first.last" -AutoReplyState disabled



* Disable Out of Office and clear the messages *
Set-MailboxAutoReplyConfiguration -Identity "first.last" -AutoReplyState disabled -InternalMessage "" -ExternalMessage ""



* Enable Out Of Office *
Set-MailboxAutoReplyConfiguration -Identity "first.last" -AutoReplyState enabled



* Create mailbox for user *
Enable-Mailbox "first.last" -Alias "first.last" -Database "exch-data-base"
set-Mailbox first.last -ApplyMandatoryProperties



* Remove an email address for a user *
Set-Mailbox -Identity "first.last" -EmailAddresses @{remove="email@isp.net"}


* Add an email address for a user *
Set-Mailbox -Identity "first.last" -EmailAddresses @{add="email@isp.net"}


* Set default SMTP address for a user *
Set-Mailbox user.name -EmailAddresses SMTP : first.last@isp.net , othermail@isp.net


* Find all accounts about to be deleted *
Get-MailboxStatistics -Database exch-data-base | Where { $_.DisconnectReason -eq "SoftDeleted" } | `
Format-List LegacyDN, DisplayName, MailboxGUID, DisconnectReason


* Show any serverside mailbox rules for a user *
Get-InboxRule -Mailbox first.last

* Move a mailbox to a new server *
New-MoveRequest -Identity first.last -TargetDatabase exch-data-base -BadItemLimit 100 -AcceptLargeDataLoss

* Show status of move *
Get-MoveRequestStatistics -Identity first.last | fl Status,StatusDetail,PercentComplete,BytesTransferred,TotalMailboxSize,BadItemsEncountered,LastUpdateTimestamp
Get-MoveRequestStatistics -Identity first.last | Format-List



===
*Adds AD Permission for mailbox to User:
Add-ADPermission "mailbox" -User "username" -AccessRights WriteProperty -Properties Personal-Information

Add-MailboxPermission -Identity "first.last" -User "first.last" -AccessRights FullAccess,DeleteItem -InheritanceType All

Remove-MailboxPermission -Identity "first.last" -User "first.last" -AccessRights FullAccess,DeleteItem,ReadPermission,ChangePermission,ChangeOwner -InheritanceType All

**Adds Send On Behalf rights
Set-Mailbox "mailbox.name" -GrantSendOnbehalfto @{Add="user.name"}
Set-Mailbox "mailbox.name" -GrantSendOnbehalfto @{Remove="user.name>"}

**sets mailbox share/regular
Set-Mailbox "mailbox display name" -Type:Regular