MicrosoftDocs · SufficientDaikon · Apr 15, 2026
@@ -228,6 +228,21 @@ items:
         href: whats-new/what-s-new-in-powershell-72.md
       - name: Migrating from Windows PowerShell 5.1 to PowerShell 7
         href: whats-new/Migrating-from-Windows-PowerShell-51-to-PowerShell-7.md
+        items:
+          - name: Script compatibility audit
+            href: whats-new/migration/script-compatibility-audit.md
+          - name: Module compatibility strategy
+            href: whats-new/migration/module-compatibility-strategy.md
+          - name: Encoding changes
+            href: whats-new/migration/encoding-changes.md
+          - name: Profile migration
+            href: whats-new/migration/profile-migration.md
+          - name: Enterprise deployment
+            href: whats-new/migration/enterprise-deployment.md
+          - name: Scheduled tasks and automation
+            href: whats-new/migration/scheduled-tasks-automation.md
+          - name: Testing and rollback
+            href: whats-new/migration/testing-and-rollback.md
       - name: Differences between Windows PowerShell 5.1 and PowerShell 7.x
         href: whats-new/differences-from-windows-powershell.md
       - name: PowerShell differences on non-Windows platforms

@@ -5,6 +5,11 @@ description: This article summarizes the differences and breaking changes from W
 ---
 # Differences between Windows PowerShell 5.1 and PowerShell 7.x
 
+> [!TIP]
+> This article is a technical reference of all differences between editions.
+> For a step-by-step migration guide, see
+> [Migrating from Windows PowerShell 5.1 to PowerShell 7][migration-guide].
+
 Windows PowerShell 5.1 is built on top of the .NET Framework v4.5. With the release of PowerShell
 6.0, PowerShell became an open source project built on .NET Core 2.0. Moving from the .NET Framework
 to .NET Core allowed PowerShell to become a cross-platform solution. PowerShell runs on Windows,
@@ -1251,3 +1256,4 @@ To opt-out of this telemetry, set the environment variable `POWERSHELL_TELEMETRY
 [34]: What-s-New-in-PowerShell-73.md
 [35]: What-s-New-in-PowerShell-74.md
 [36]: What-s-New-in-PowerShell-75.md
+[migration-guide]: ./Migrating-from-Windows-PowerShell-51-to-PowerShell-7.md
@@ -0,0 +1,260 @@
+---
+description: >-
+  Understand how default encoding changed from Windows PowerShell 5.1 to
+  PowerShell 7 and choose a migration strategy for your scripts.
+ms.date: 04/15/2026
+title: Encoding changes in PowerShell 7
+---
+
+# Encoding changes in PowerShell 7
+
+PowerShell 7 changed the default encoding for file output from
+locale-dependent encodings (such as Windows-1252) and UTF-16LE to UTF-8
+without a byte order mark (BOM). This change aligns with modern tooling and
+cross-platform expectations, but it can break scripts that depend on specific
+encodings.
+
+## What changed
+
+### Default encoding comparison
+
+The following table shows the default encoding for common cmdlets and
+features in each edition:
+
+| Cmdlet or feature | Windows PowerShell 5.1 | PowerShell 7 |
+| ----------------- | ---------------------- | ------------ |
+| `Out-File` / `>` operator | UTF-16LE with BOM | UTF-8 without BOM |
+| `Set-Content` | System locale (often Windows-1252) | UTF-8 without BOM |
+| `Add-Content` | System locale | UTF-8 without BOM |
+| `Export-Csv` | ASCII | UTF-8 without BOM |
+| `Export-Clixml` | UTF-8 with BOM | UTF-8 without BOM |
+| `New-ModuleManifest` | UTF-16LE with BOM | UTF-8 without BOM |
+| `Start-Transcript` | UTF-8 with BOM | UTF-8 without BOM |
+| `$OutputEncoding` (pipe to native) | ASCII | UTF-8 without BOM |
+
+### The -Encoding parameter
+
+In Windows PowerShell 5.1, the `-Encoding` parameter accepted string values
+such as `UTF8`, which produced UTF-8 _with_ BOM. In PowerShell 7, the
+parameter accepts `System.Text.Encoding` objects and string values with
+updated meanings:
+
+| Value | PowerShell 7 behavior |
+| ----- | --------------------- |
+| `utf8` | UTF-8 without BOM |
+| `utf8BOM` | UTF-8 with BOM |
+| `utf8NoBOM` | UTF-8 without BOM (same as `utf8`) |
+| `utf16` or `unicode` | UTF-16LE with BOM |
+| `utf16BE` or `bigendianunicode` | UTF-16BE with BOM |
+| `ascii` | ASCII (7-bit) |
+| `oem` | OEM code page |
+| `ansi` | ANSI code page |
+
+### Removed: -Encoding Byte
+
+The `Byte` encoding value was removed in PowerShell 7. Use the
+`-AsByteStream` parameter instead:
+
+**Before (Windows PowerShell 5.1)**:
+
+```powershell
+Get-Content -Path file.bin -Encoding Byte
+```
+
+**After (PowerShell 7)**:
+
+```powershell
+Get-Content -Path file.bin -AsByteStream
+```
+
+## Impact assessment
+
+### Scripts that generate files for other tools
+
+If your scripts use `Out-File`, `Set-Content`, `Export-Csv`, or the `>`
+operator to create files that are consumed by other tools, check whether
+those tools expect a specific encoding.
+
+Common scenarios that break:
+
+- **SIEM or log analysis tools** that detect file type by BOM. UTF-16LE
+  files have a `0xFF 0xFE` BOM; PowerShell 7's UTF-8 files have no BOM.
+- **Legacy Windows tools** that expect the system locale encoding
+  (such as Windows-1252 for Western European systems).
+- **Signed scripts** where the encoding affects the digital signature.
+  Re-sign scripts after changing encoding.
+
+### Scripts that read files from Windows PowerShell
+
+If your PowerShell 7 scripts read files that were created by Windows
+PowerShell 5.1, encoding detection generally works correctly. PowerShell 7
+detects the BOM in UTF-16LE files and reads them without issues. Files
+without a BOM are read as UTF-8.
+
+### Pipe-to-native-command changes
+
+The `$OutputEncoding` variable controls the encoding when PowerShell pipes
+text to native commands. It changed from ASCII to UTF-8:
+
+- **ASCII** (Windows PowerShell 5.1): Characters outside the 7-bit ASCII
+  range were replaced with `?`.
+- **UTF-8** (PowerShell 7): Extended characters are preserved but may
+  appear garbled if the native command doesn't support UTF-8.
+
+If you pipe output to legacy tools like `cmd.exe /c findstr` and see
+garbled characters, set `$OutputEncoding` to ASCII in your session or
+profile:
+
+```powershell
+$OutputEncoding = [System.Text.Encoding]::ASCII
+```
+
+## Migration strategies
+
+### Strategy 1: Embrace UTF-8
+
+UTF-8 is the dominant encoding for modern tools, web APIs, cross-platform
+scripts, and version-controlled files. If possible, update all consumers to
+expect UTF-8 without BOM.
+
+To re-encode existing files in bulk:
+
+```powershell
+Get-ChildItem -Path .\output -Filter *.csv -Recurse | ForEach-Object {
+    $content = Get-Content -Path $_.FullName -Raw
+    [System.IO.File]::WriteAllText(
+        $_.FullName,
+        $content,
+        [System.Text.UTF8Encoding]::new($false)
+    )
+}
+```
+
+### Strategy 2: Force legacy encoding in PowerShell 7
+
+If you can't update consuming tools, force the old encoding defaults in your
+PowerShell 7 profile using `$PSDefaultParameterValues`:
+
+```powershell
+# Restore Windows PowerShell 5.1 encoding behavior
+$PSDefaultParameterValues['Out-File:Encoding'] = 'utf8BOM'
+$PSDefaultParameterValues['Set-Content:Encoding'] = 'utf8BOM'
+$PSDefaultParameterValues['Add-Content:Encoding'] = 'utf8BOM'
+$PSDefaultParameterValues['Export-Csv:Encoding'] = 'utf8BOM'
+$PSDefaultParameterValues['Export-Clixml:Encoding'] = 'utf8BOM'
+```
+
+> [!IMPORTANT]
+> Setting `$PSDefaultParameterValues` in a profile affects all scripts in
+> that session. For targeted control, set the encoding per-script instead.
+
+### Strategy 3: Explicit encoding per script
+
+For scripts that must work in both Windows PowerShell 5.1 and PowerShell 7,
+always specify the `-Encoding` parameter explicitly:
+
+```powershell
+$data | Export-Csv -Path report.csv -Encoding UTF8 -NoTypeInformation
+```
+
+> [!NOTE]
+> The value `UTF8` produces UTF-8 _with_ BOM in Windows PowerShell 5.1 and
+> UTF-8 _without_ BOM in PowerShell 7. If you need identical output in both
+> editions, use `[System.Text.UTF8Encoding]::new($true)` (with BOM) or
+> `[System.Text.UTF8Encoding]::new($false)` (without BOM) as the
+> `-Encoding` value.
+
+## BOM considerations
+
+### When BOMs are required
+
+- XML files consumed by tools that require a BOM to detect encoding
+- Signed PowerShell scripts (re-encode and re-sign after migration)
+- Interop with older Java versions that expect a UTF-8 BOM
+- Files read by applications that default to the system locale without BOM
+  detection
+
+### When BOMs cause problems
+
+- Unix and Linux tools (many treat the BOM as visible characters)
+- Git diff output (BOM appears as invisible changes at the start of files)
+- JSON parsers (the JSON specification prohibits BOMs)
+- Shell scripts on non-Windows platforms
+
+### PowerShell 7 reads BOMs correctly
+
+Regardless of the default output encoding, PowerShell 7 detects and
+respects BOMs when _reading_ files. A file created with UTF-16LE BOM by
+Windows PowerShell 5.1 is read correctly by PowerShell 7.
+
+## Verify encoding in your environment
+
+Use the following function to check the encoding of a file by inspecting
+its first few bytes:
+
+```powershell
+function Get-FileEncoding {
+    param(
+        [Parameter(Mandatory)]
+        [string]$Path
+    )
+
+    $bytes = [byte[]](
+        Get-Content -Path $Path -AsByteStream -TotalCount 4
+    )
+
+    if ($bytes.Length -ge 3 -and
+        $bytes[0] -eq 0xEF -and
+        $bytes[1] -eq 0xBB -and
+        $bytes[2] -eq 0xBF) {
+        'UTF-8 with BOM'
+    }
+    elseif ($bytes.Length -ge 2 -and
+            $bytes[0] -eq 0xFF -and
+            $bytes[1] -eq 0xFE) {
+        'UTF-16 LE (BOM)'
+    }
+    elseif ($bytes.Length -ge 2 -and
+            $bytes[0] -eq 0xFE -and
+            $bytes[1] -eq 0xFF) {
+        'UTF-16 BE (BOM)'
+    }
+    else {
+        'No BOM (UTF-8 or ASCII)'
+    }
+}
+```
+
+Scan a directory of output files:
+
+```powershell
+Get-ChildItem -Path .\output -File | ForEach-Object {
+    [PSCustomObject]@{
+        File     = $_.Name
+        Encoding = Get-FileEncoding -Path $_.FullName
+    }
+}
+```
+
+## Quick reference
+
+| I need to... | Use this |
+| ------------ | -------- |
+| Write UTF-8 without BOM (PS 7 default) | `Out-File -Path file.txt` |
+| Write UTF-8 with BOM (match WinPS default) | `Out-File -Path file.txt -Encoding utf8BOM` |
+| Write UTF-16LE with BOM (match WinPS `>`) | `Out-File -Path file.txt -Encoding unicode` |
+| Read binary data | `Get-Content -Path file.bin -AsByteStream` |
+| Force ASCII for native pipe | `$OutputEncoding = [System.Text.Encoding]::ASCII` |
+
+## Next steps
+
+- [Migrate PowerShell profiles][profile-migration]
+- [Audit scripts for PowerShell 7 compatibility][script-audit]
+- [Migrating from Windows PowerShell 5.1 to PowerShell 7][migration-guide]
+- [Differences between Windows PowerShell 5.1 and PowerShell 7.x][differences]
+
+<!-- link references -->
+[differences]: ../differences-from-windows-powershell.md
+[migration-guide]: ../Migrating-from-Windows-PowerShell-51-to-PowerShell-7.md
+[profile-migration]: ./profile-migration.md
+[script-audit]: ./script-compatibility-audit.md