How to reset/hack Mac password.

For certain versions the easiest way is to use the Installer CD method.

However, if you don't have an installer CD you can do some command-line tricks instead.
Boot up the computer, holding Command+S as you hear the startup chime.
The Mac will boot into single user mode, giving you a command prompt after loading everything up.

If the Mac is running Snow Leopard or below, type the following commands, hitting Enter after each one and waiting for the prompt to come up again before running the next one:

/sbin/fsck -fy
/sbin/mount -uw /
launchctl load /System/Library/LaunchDaemons/
dscl . -passwd /Users/

Renew a self-signed certificate in Exchange

If a certificate has exired (shows exipred in the event logs) then you need the thumbprint. Can find this on the outlook web access->rightclick->properties->certificates->thumbprint.

Open exchange cli:

-lets you see a list of all the current certificates and their thumbprints.

If the certificate isn't expired, try this:

get-exchangecertificate -thumbprint
XXXXXxxxxxxxxxxxxxxXXXXX | enable-exchangecertificate
-services "IIS,SMTP"

If the certificate HAS expired (as it says it has in the event
description: "The existing certificate for that FQDN has expired"),
and the certificate is "self signed" then you should be able to renew
the cert like this:

Stuck RDC session on remote server, or log off remote RDC user session.

Here's how to easily fix an issue where either a remote RDC session is stuck, preventing you from logging onto a server, or you want to log a remote user off of a remote server session for any reason:

First, check the session number with qwinsta:

Write down the session ID.

Then use the logoff command:

Disk Cleanup WinSxS folder in Windows Server 2012 (R2) using DISM

Here is how to clean up the WinSxs folder on Windows Server 2012 R2, to reclaim disk space.
This will delete superseded updates and unused system files to free up extra disk space.
It uses dism.exe‘s disk cleanup options.

Often the Windows component store folder(C:\Windows\WinSxS) will take up a lot of space on your servers. This folder contains all the files that are required for a Windows installation as well as any updates to those files are also held within the component store as the updates are installed

Here's how to use the DISM tool to safely free up space:

The basic command we use it: Dism.exe /online /Cleanup-Image. This has the following extra options:

/ResetBase with /StartComponentCleanup

Open a PowerShell as Administrator, then:

Office 365 2016 Word, excel lagging, slow typing.

There seems to be an issue with version 1706 (build 8229.2086) which causes lagging/slow typing on certain types of documents with images/templates.

As a temporary workaround, roll back to an earlier version of O365 office:

Disable office updates:
In word->File->Account
Check your version of Word
Switch off automatic updates.

To roll back to an earlier version:

Open an elevated command prompt and run the following commands:

cd %programfiles%\Common Files\Microsoft Shared\ClickToRun
officec2rclient.exe /update user updatetoversion=16.0.xxxx.yyyy

Where xxxx.yyyy is soemthing like 8201.2075 (seem to fix the issue)

Remember to tuen updates back on at a future point and restore Office to the latest version once the issue has been resolved.