Computer Guide

Reducing image size for mailing

by George Skarbek - 26 February 2008

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Reducing image size for mailing

Q: Is there some software (preferably free) that reduces 2.5-3 MB photograph files to a smaller size that I can email on dialup?  These are photos received, not my own.  I am using Windows XP but can find nothing there to help

A: As this is a common problem, there are many programs that can do what you want.  One good starting point is to download the small but excellent program, IrfanView, from  When viewing your image press Ctrl + r or click on Image, Resize / Resample and assuming that your recipients will just look at the image on the screen, select 800 x 600 pixels and also in the DPI box enter 72.

When saving the image you must give it another name or you will overwrite your original file with this reduced image. IrfanView will warn you if you forget. Finally in the Save Quality select a value of between 75 and 80%. My guess is that your resultant image will be less than 5% of the original size but will look identical on the screen. However, if your recipients want to print A4 size then a significantly lesser reduction in image size will be required.

Picasa from  is another good free product to consider that will automatically resize images for e-mail as well have having many other good features.


Password protecting a file

Q: How can I put a password on to a particular file so that it is only ever Read Only and, if it is copied it remains Read Only, so that no one in my absence from whatever cause, can get the bright idea of amending it before they print it off. 

A: There is no way in Windows XP to password protect a file and removing the read-only attribute is easy if anyone wishes to do this.

For password protection I suggest WinZip, or the free 7-Zip. If it is a Word or Excel file then use Microsoft’s encryption to prevent either opening or modifying it. For Word this done from File, Save As then click on the Tools drop-down menu for Options then click on Security and you can put a password to modify or to open.

Adjusting Spam filters

Q: The Consumer magazine CHOICE send out a bi-monthly newsletter to all online subscribers. I have never received this and have been advised by the Consumer organisation "Please check your spam filters because they could be getting blocked." How do I do this please? I use Microsoft Outlook and McAfee Viruscan and Firewall.


A: This is not being prevented by the firewall, which is designed to stop human hackers from accessing your computer, nor by the anti-virus software as Viagra ads and Nigerian offers to give you millions which are not viruses.  As the Choice article has similar attributes to other unwanted commercial mail, you have to add the sender’s address to the anti-spam filter. This may be done by some other anti-spam software on your computer or if your ISP has applied the filter to minimise your flow of spam mail. Many ISPs will allow you to have your own ‘white list’ which will allow publications such as Choice or the Economist not to be stopped as spam.


To look at the e-book in PDF format, Computer Guide, based on these columns click here