The worldwide chaos arising from CrowdStrike’s misbegotten upgrade of IT systems confirms my view that “upgrade” has become one of the most feared words in the English language, possibly even more than “Trump” (Slow recovery from IT outage begins as experts warn of future risks, 20 July).
Robert Parkhill
London
• On behalf of the computer illiterates who just heard the word “Windows” and froze, is it safe to turn on our computers yet? My email was hacked last month and I am still not fully recovered. Sent from my phone…
Margaret Squires
St Andrews, Fife
• Re how to fight back on water bills (Letters, 22 July), my strategy was to email my water supplier, Affinity, asking for a refund on the sewage disposal bill it charged on behalf of Thames Water, which had failed to dispose of the sewage properly. It told me that it was a Thames Water problem. After a couple of phone calls and emails to Thames Water, I received a cheque for £30 in compensation.
Barry A Coomber
London
• Dr Craig Hambling (Letters, 22 July) states that he is “a medieval historian of education and physical training”. Clearly his vocation leads to remarkable longevity. We should all take note.
David Horwell
Harpenden, Hertfordshire
• Last week, when out shopping, the sole of my sandal suddenly came unstuck and an elderly lady, seeing my predicament, delved into her bag and produced a rubber band (Letters, 22 July). I managed to secure sole to upper and got home safely, though with a strange gait.
Viv Rose
Southampton
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