Hide cell contents with semicolons

In Excel, you can use semicolons in Format Cells to control whether or not text and numbers are displayed.

Entering two semicolons in the Custom category on the Number tab will hide the contents of any cells which contain only positive or negative numbers:

Entering three semicolons will hide the text and numbers:

How deleted emails are recovered in Exchange

See a good guide here on the Microsoft site on how a deleted email which is missing from the Deleted Items folder can still be recoverable.

In Exchange, an admin can access 'in place eDiscovery & hold' under Compliance Management. The admin will be able to select specific email accounts to search through.

Microsoft provides a detailed diagram showing how keyword searches can be entered to search through the mailboxes of multiple custodians. Note that you have the option to run proximity searches, and can restrict the search to a particular date range.

Tracking pixels

An image embedded in an email must be downloaded off a server by the recipient. This allows the sender to determine exactly

when an email message is opened. Images will often be added surreptitiously and can be transparent. The general concept is known as a web beacon or tracking pixel. It can be made to work not only with images but other elements of HTML.

The pixel will disclose the IP address to help pinpoint the recipient’s location.

Email software can be set to prevent the downloading of images from servers. In Outlook, go to File . . . Options . . . Outlook Options. In the Trust Center‘s ’Automatic Download’ tab check off the boxes labeled “Don’t download pictures automatically in standard HTML email messages or RSS items” and “Don’t download pictures in encrypted or signed HTML email messages.”