Password Prompt from Mail Server

Question

I keep getting prompted by my mail server:
The POP server “mail.username.com” rejected the password for user “[email protected]”
Yet the correct password does not work. This is an on and off problem, 2 hours here then OK, one day there then OK! The problem in spite of endless live chats with my host provider, I thought it was a host server issue, however I have just changed host, and still the problem continues!!
On Mac support the only case similar is an Apple share topic, and it suggests emtpying the casche on the server side!!
Anyone??
Simon

Answer 1

Open /Applications/Utilities/Keychain Access, choose Keychain First Aid from the application menu, and proceed to repair the keychain. If that doesn’t work, you may try removing the password entry from the keychain and letting Mail create it again the next time it asks for it.
Note, however, that Mail often doesn’t correctly report what the problem really is. If Mail can connect to the server but cannot log into your mail account for some reason, it’ll ask for your password regardless of whether that’s really the problem or not. Don’t keep entering the password every time — just click Cancel instead, and take the account back online afterwards.
Some ISPs refuse connection attempts if they are too frequent, for example, or limit the number of simultaneous connections that are allowed from the same IP address, or there may be too many messages on the server and Mail times out before the server responds, or there might be a problem with the network, or there might be a problem with the server...
Do you access this account from more than one computer or some other way (e.g. webmail) while Mail is checking for mail?
What’s the time interval chosen in Mail > Preferences > General > Check for New Mail? If it’s set to Every minute, try changing it to Every 5 minutes.
If this is a POP account, what are your Preferences > Accounts > Remove copy from server settings?
Go to Apple Menu > System Preferences > Network, choose Network Port Configurations from the Show popup menu, and make sure that the configuration used to connect to Internet appears at the top of the list. Leave checked (enabled) only the port configuration needed to connect to Internet and Built-in Ethernet (in that order if not the same), uncheck (disable) the rest of network port configurations and see whether that helps — if it doesn’t, turn ON again the ones you want enabled.
Try using a different method to connect to Internet, if possible, or connecting the computer to Internet as directly as possible (i.e. bypassing any routers that might be present, using an ethernet cable instead of wireless, etc.), or shutting down both the computer and the router/modem used to connect to Internet, restarting, and see whether that makes a difference.