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Category: Windows

Microsoft Windows Operating Systems

Linux TCP Flaw Fix

For those who want to know all the details here is a document which explains how this RFC 5961 flaw can be exploited:

http://www.cs.ucr.edu/~zhiyunq/pub/sec16_TCP_pure_offpath.pdf

The fix itself:

net.ipv4.tcp_challenge_ack_limit = 999999999

which is appended to

/etc/sysctl.conf file using a text editor

and applied with

sysctl -p

Most importantly a command to show if your Linux OS is patched already – I had to trawl quite a bit to find this https://community.centminmod.com/threads/linux-tcp-flaw-cve-2016-5696-allows-hackers-to-hijack-net-traffic-inject-malware-remotely.8304/

sysctl -a | grep ack_limit
net.ipv4.tcp_challenge_ack_limit = 100

As you can see from above it was set to 100 on my desktop running Ubuntu 14.04 with all the updates on 18/08/16.

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Windows 10 No Start Menu

No Start Menu when you click Start button and right-click not working on Taskbar program launch icons.

Try clicking on on Notifications icon (bottom RH corner) and toggle off Tablet Mode

Windows SP1 Convenience Rollup

The Windows SP1 Convenience Rollup (WSCR) updates a clean copy of Windows SP1 from  Feb 2011 to May 2016. Further updates are then installed as normal

Steps

  1. Install a clean copy of Windows 7 SP1
  2. Install April 2015 Servicing Stack Update from https://support.microsoft.com/en-us/kb/3020369 and click the appropriate “Download the package now” link
  3. Go to http://catalog.update.microsoft.com/v7/site/Search.aspx?q=KB3125574  and click the Install button at the bottom of the page; click Yes and click the Add button for your version of Windows from the 3 choices shown.

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Rename Windows Home Folder

The examples given change the user’s home folder from Michael to John.

In case of mistakes and recover data you may have missed make an image backup. Additionally create a restore point to backup the registry.

Method 1 – create new user and delete the old one

The recommended approach. It’s a bit sledge-hammer but is reliable and has the benefit of cleaning up the user profile.

  1. Create a new account called John using Control Panel or Windows 10 PC Settings >

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Firefox about:config Locale Settings

In Firefox URL box enter about:config to view | edit your default locale search and language settings:

  • general.useragent.locale
  • browser.search.countryCode
  • browser.search.region
  • browser.search.isUS

UK values for above  = en.GB, GB, GB, False

Use Windows Check Disk to Repair Your Drive

Sometimes, your computer is noticeably slower or programs “hang” when you access certain files or upgrades fail or programs just won’t run. This odd behaviour might occur because there is corruption of within the files system on your hard disk drive.

You can troubleshoot the problem by using the Windows Disk Check tool called CHKDSK.  Check Disk can identify and automatically correct file system errors and make sure that you can continue to load and write data from the hard disk. You can use Check Disk in all versions of Windows not only for local hard drives,

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Windows Image Backup

Insert your portable USB drive into a free USB port. If you have USB 3 port (marked SS Super-Speed and blue inside) use this in preference to a USB 2 port to get a much faster backup.

Windows 10

Click Start button (Bottom LH corner) and select Settings Cog just above Power icon. In Settings select “Update Security” > “Backup” > “Go to backup and Restore (Windows 7) “. This will bring up the “Backup or restore” window below.

Windows 7

Click the Windows 7 Start button (bottom left corner) and type “backup”

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Windows “Checking for updates” never ends

Checking For Updates

After installing a new copy of Windows 7 SP1 the first Windows Update can take several hours “Checking for Updates…” and appears to be hung. However, don’t give up. It is processing over 200 updates! The time it takes to complete depends on the speed of your Internet connection and computer. Times can be up to 1 hr.

To avoid the frustration of waiting try to run this first update overnight. Ensure you have set Disk Sleep to “Never” within Control Panel | Power Options to avoid it sleeping mid-way through.

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Backup using FreeFileSync

FFS Dialog

FreeFileSynch (FFS) can be directly downloaded and installed from the author’s site:  http://www.freefilesync.org/. FFS is a free Open Source application for backing up and restoring user files and folders on Windows, Linux and Mac operating systems. One of the major benefits is that once the first backup has been completed only changes are backed up making subsequent backups faster. Also it supports USB backup drive names, e.g. [My Passport] as targets rather than relying on a drive letter which can change depending on which port the USB cable is plugged into,

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