Thomas' Tech Tips

Show network places in Explorer navigation pane

Wed, 24 Dec 2025 00:00:00 +0100

I recently found myself on a Windows computer on which Network Places did not appear in the navigation pane.

The registry entry below will restore Network Places in the navigation pane of Windows Explorer.

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\CLSID\{F02C1A0D-BE21-4350-88B0-7367FC96EF3C}\ShellFolder]
"Attributes"=dword:b0040064
"FolderValueFlags"=dword:00102240

Copy this code to a text file and save as restore-network-places.reg.

Then doubleclick the file to load it to registry.

Alternatively, you can use regedit.exe to manually make the change to registry.

Take ownership of files and folders in Windows

Wed, 17 Dec 2025 00:00:00 +0100

I often utilize Windows Performance Counters to log Windows performance metrics. By default, these counters log to C:\PerfLogs as the SYSTEM user. This results in the log files only being accessible by the SYSTEM account or Administrators group.

Here are commands to take ownership of those folders:

takeown /F "C:\PerfLogs" /R /D Y

/F specifies the folder.
/R makes it recursive.
/D Y assumes “Yes” for any prompt.

icacls “C:\PerfLogs” /grant YourUserName:F /T`
/grant gives permissions.
F = Full control.
/T applies to all subfolders and files.

You can verify the permissions using this command:

icacls "C:\PerfLogs"`

You should see your user listed with (F).

Alternative approach

Changing ownership from SYSTEM to your user may affect system monitoring logs. If you want to keep SYSTEM as owner but still have access, you can add your user to ACL without changing ownership:

 icacls "C:\PerfLogs" /grant YourUserName:F /T

(Skip takeown in that case.)

Disable Windows 11 New Context Menu

Wed, 10 Dec 2025 00:00:00 +0100

With Windows 11, Microsoft made the Windows Explorer context menu less useful by deciding to only show some of the options in the context menu when you right click. Then presenting a “Show more options” menu item that when clicked will show the old context menu. Needless to say, this is breaks muscle memory and keyboard shortcuts.

Luckily, it is quite easy to restore the old context menu with a registry tweak.

The following registry tweak will restore the old Windows Explorer context menu:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Classes\CLSID\{86ca1aa0-34aa-4e8b-a509-50c905bae2a2}\InprocServer32]
@=""

Copy this code to a text file and save as disable-new-context-menu.reg.

Then doubleclick the file to load it to registry.

Alternatively, you can use regedit.exe to manually make the change to registry.

Create publicly readable S3 Bucket and access token to use from app via API

Wed, 03 Dec 2025 00:00:00 +0100

Create the bucket

In AWS Console, open the S3 service.

Click Create Bucket.

Enter Name and Region.

Under Object Ownership, select ACLs enabled (This is sometimes needed for legacy public access, though Bucket Policy is the preferred method).

Under Block Public Access settings for this bucket, uncheck “Block all public access” and confirm the warning.

Click Create bucket.

Add a Bucket Policy (Public Read Access)

Open the new bucket and go to the Permissions tab.

Scroll to the Bucket policy section and click Edit.

Paste the following JSON, replacing your-bucket-name with your actual bucket name:

{
	"Version": "2012-10-17",
	"Statement": [
		{
			"Sid": "PublicReadGetObject",
			"Effect": "Allow",
			"Principal": "*",
			"Action": "s3:GetObject",
			"Resource": "arn:aws:s3:::your-bucket-name/*"
		}
	]
}

Click Save.

Confirm the warning that bucket is public.

Create IAM User and Access Key

In AWS console, open IAM service

Go to Policies and click Create policy.

Select the JSON tab and paste the following, replacing your-bucket-name with your actual bucket name. This grants minimum permissions for listing the bucket and uploading files.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:PutObject",
                "s3:PutObjectAcl" 
            ],
            "Resource": "arn:aws:s3:::your-bucket-name/*"
        },
        {
            "Effect": "Allow",
            "Action": "s3:ListBucket",
            "Resource": "arn:aws:s3:::your-bucket-name"
        }
    ]
}

Click Next: Tags, then Next: Review. Name the policy (e.g., AppS3UploadPolicy) and click Create policy.

Create IAM User and Attach Policy:

Go to Users and click Create user.

Enter a User name (e.g., AppUploader).

For AWS access type, select Access key - Programmatic access.

Click Next

On the Permissions page, select Attach existing policies directly and search for and select the AppS3UploadPolicy you just created.

Click Next: Tags, then Next: Review and Create user.

Retrieve Access Key/Secret Key:

The final screen will show the Access key ID and Secret access key.

Crucially, copy and securely save both of these. They will not be shown again. These are the credentials your app will use for uploading.

Connect multiple SQLite database files using ATTACH

Tue, 04 Nov 2025 00:00:00 +0100

ATTACH allows you to attache another database file to the current connection.

Example:

ATTACH 'external.db' AS ext;

This makes it possible to join tables from different databases.

Example:

$ sqlite3 main.db
ATTACH sales.db AS sales;
SELECT
    e.employee_name,
    s.sale_amount
FROM
    employees AS e
JOIN
    sales.sales AS s ON e.employee_id = s.employee_id
WHERE
    s.sale_date > '2025-01-01';

Portscan using PowerShell

Tue, 28 Oct 2025 00:00:00 +0100

How to test if a network port is reachable with PowerShell?

PS C:\Users\sdktda> Test-NetConnection -ComputerName example.com -port 80


ComputerName     : example.com
RemoteAddress    : 10.0.0.50
RemotePort       : 80
InterfaceAlias   : Ethernet 9
SourceAddress    : 10.0.0.2
TcpTestSucceeded : True

PowerShell equivalent to cut

Tue, 21 Oct 2025 00:00:00 +0200

How to do the equivalent of Linux’ cut on Windows using PowerShell? This is how:

$filename = "sample.cfg"

Get-Content $filename | ForEach-Object {
    $_.split(":")[1]
}

PowerShell equivalent to wc -l

Tue, 14 Oct 2025 00:00:00 +0200

How do you count lines in a file or from output of a command?

On Linux, it is easy: just use wc -l but how to do it with PowerShell?

This is how:

(ls | Measure-Object -line).Lines

For example count number of active TCP connections

(netstat -na | Select-String ESTABLISHED | Measure-Object -line).Lines

PowerShell equivalent to grep

Tue, 07 Oct 2025 00:00:00 +0200

How do you grep on PowerShell? Well, I know of two ways: findstr and Select-String:

netstat -na | findstr "PORT"
netstat -na | Select-String "PORT"

Using regular expression patterns:

findstr /i "^foo.*bar$" file.txt
Select-String "^foo.*bar$" file.txt

Detect ECC memory errors on Linux

Tue, 30 Sep 2025 00:00:00 +0200

How to detect and monitor for ECC RAM errors on Debian Linux.

ECC RAM can detect and correct simple bit-flip errors caused by cosmic radiation, etc.

It is useful to be able to detect and monitor for ECC errors.

Linux supports logging ECC errors via the Error Detection and Correction driver (EDAC).

In Debian, the following tools are available:

edac-utils (although it is mostly deprecated)
rasdaemon

rasdaemon monitors for and reports ECC errors.

ECC error messages typically includes:

The memory address in which the error was detected.
DRAM address (column, row, rank, bank)
Channel
DIMM slot number

The amount of defails varies significantly between the different CPU models and memory controllers.

Installing rasdaemon on Debian

apt install rasdaemon

Querying for EEC errors

~ # ras-mc-ctl --summary
No Memory errors.

No PCIe AER errors.

No Extlog errors.
No MCE errors.


~ # ras-mc-ctl --error-count
Label                   CE      UE
mc#0csrow#1channel#0    0       0
mc#0csrow#0channel#1    0       0
mc#0csrow#3channel#0    0       0
mc#0csrow#2channel#0    0       0
mc#0csrow#0channel#0    0       0
mc#0csrow#3channel#1    0       0
mc#0csrow#2channel#1    0       0
mc#0csrow#1channel#1    0       0