The strength of passwords is dependent on the difficulty to crack them. I recently couldn't access my email. I assumed it was because someone was trying to hack the account. In the past I know that if I enter a password several times wrong I have to wait some time to try again only after my browser is closed and opened again. That is a good security feature. It's annoying not to be able to get into the account but necessary to prevent hacking. Just as important is having an excellent password difficult to hack. Special characters !@#$%^&* are a good way to make the password more uncrackable. We are only allowed a "-" or "_". Fearing that it was someone trying to hack my account I had to make an extremely long password with those characters included. It also was very difficult for me to type in without errors. I can easily remember it but having special characters to work with would have made it easier to type since I could make it shorter. After I changed the password I was able to get into my account.
ATT should really allow special characters in its passwords. I have been reading about programs that hack email accounts and passwords and really it was shocking and eye opening.
Thanks. I hope that there are no really "good" reasons for limiting the number of special characters. I have read about servers being attacked and the hashes that confirm the passwords are stolen. From the hashes the hacker can get the passwords if they have enough time and motivation. The one good defence for the account holders is to have stronger passwords that can't be broken from the hashes so easily.