Tag Archives: Windows

Disappearing folder – bug in Windows 7

In process of testing one of our automation software I hit interesting Windows 7 bug. First I found it in our software, and right away tested this scenario on Windows 7, and bug was there.

The bug. Create folder on the Desktop.

Right click on Desktop
New folder

New folder appears and cursor blinks allowing to change the name for the folder.

Cursor at the end

Place cursor at the end of folder name, and enter dot (.) character.

Dot at the end

After pressing Enter key the folder disappears.

Folder disappears

But do not worry, it will come back after reboot, or after refresh (F5 key).

After refresh

Appears that this bug/behavior… that only Windows 7 is affected. Other Windows versions I tested does not have this bug, even Windows XP and upcoming Windows 8 behaves correctly (see screenshots at the end of the post).

A side note. By “correctly” in this case I mean, that folder does not disappear, however perhaps, there is another bug. The dot “.” character disappears in all Windows versions. This of course depends on interpretation, for example, I also tested this on Ubuntu 10, and Ubuntu (and probably most nixes) allows dot (.) at the end of filename.

Why this happens? Every filename consists of two parts: filename and extension. These two parts are separated by dot (.) character. Windows Shell hides this dot from you, and when you enter “filename.”, it thinks, that this must be a filename without extension, so it stores only filename. In theory you should be able to trick shell by adding more dots, like “filename…”, but Windows 7 Shell reduces them to no dot. Of course you can create file or folder with one or more dots at the end, but for this you will need a normal file manager, like Far Manager (which is open source). Also, keep in mind, that you will not be able to delete this file or folder from desktop using Windows Shell, you will need to switch to file manager again.

Note 1. Windows Server 2008 R2 is based on the same codebase, so it has the same bug.
Note 2. Operating Systems used in the test:

  • Windows 7 Professional 64-bit
  • Windows Vista Enterprise
  • Windows Server 2008 Enterprise
  • Windows Server 2008 R2 Datacenter
  • Windows Server 2003 Enterprise
  • Windows 8 Consumer preview
  • Windows XP
  • Ubuntu 10

When Windows automatic update suddenly stops updating Windows automatically

Recently we noticed that some of our test and dev servers were not updating automatically through Windows or Microsoft update.

It was real pain to find why this happened. There are numerous threads in the Internet about failed Windows update, and it is very hard to find the right answer. Luckily, I found a post in CNET forum from Jim Sheehy from Sequel Data Systems. He supports more than 800 desktops and he is writing about three possible causes of Windows update failure:

  1. The Windows Update Temporary folder is corrupted. (%windir%\SoftwareDistribution)
  2. Update Agent 3.0 is not installed properly. (Download latest Update Agent)
  3. Installer 3.1 is corrupted. (Reinstall Windows Installer 3.1 or …)

Read more at CNET forum: Help! My Windows automatic updates suddenly stopped working.

Microsoft’s PowerShell hangs when output is captured using Windows API

I was debugging a program that uses Windows API (Creating a Child Process with Redirected Input and Output) to capture stdout of Microsoft’s Windows PowerShell.

Script passed to PowerShell (-File switch) didn’t execute and PowerShell just hanged until killed by Task Manager.

It turns out that you need to use undocumented parameter “-InputFormat none”:
C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -InputFormat none -File file.ps1

This is discussed in MS Connect site: PowerShell.exe can hang if STDIN is redirected.

Similar issue at StackOverflow: Silently executing a PowerShell script from WiX Hangs PowerShell.