Effect of Proxy settings on checking for mail

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Joined: March 14th, 2014, 3:48 am

Post Posted April 13th, 2015, 4:20 am

I have 2 desktops running Windows 8 and a Dell laptop running Windows 8.1. I'm running Thunderbird 31.6 on all three.

Originally all 3 were running Windows 8 but I figured I'd give Windows 8.1 a try on the laptop. I did this upgrade about 6 months ago.

Before doing the upgrade on the laptop Thunderbird was running perfectly. As soon as I did the Windows 8.1 upgrade I ran into a problem getting Thunderbird messages to download as soon as I opened the program. I have 4 email addresses on the laptop with a medium amount of stored messages in folders set to automatically compress. The two desktop computers have far more messages stored in their folders and there is no problem getting mail to download immediately at startup. No messages are left on the servers on any of the 3 systems.

To get mail to download the quickest possible way on the laptop I had to set one email address ( to SERVER SETTING, CHECK FOR MAIL AT STARTUP and the other 3 addresses NOT to check for mail at startup. Then the earthlink address would only take 3 or 4 seconds to do the check and download messages. Once that was done I could click on GET MESSAGES, GET ALL NEW MESSAGES on the drop down menu and all addresses would download immediately. If I had the server setting for all 4 addresses set to CHECK FOR NEW MESSAGES AT STARTUP then it could take 15 to 20 seconds for mail to download and Thunderbird would be locked up for that period of time. If I had no addresses set to check for messages at startup then the program would start as it should but as soon as I clicked on CHECK FOR ALL NEW MESSAGES in the drop down window the program would freeze for that 15 to 20 seconds.

Over the past 6 months I tried many things to solve the problem that did not work. The problem persisted no matter what version of Thunderbird was installed. I tried standard and beta versions all the way back to around 22.0 and up to the current beta and standard versions.

The other day I was again searching for a solution to this problem and stumbled upon a site that talked about TOOLS, OPTIONS, ADVANCED and then DISK SPACE and COMPACTING settings. After working with this for a few minutes and getting nowhere I tried for the first time changing the PROXY settings in the same window.

VOILA !!!! Problem finally solved. As soon as Thunderbird starts all 4 email addresses are immediately checked and messages downloaded just as on the 2 desktop PCs. There is no freezing of Thunderbird's just simply working correctly.

The change I made was in CONFIGURE HOW THUNDERBIRD CONNECTS TO THE INTERNET, SETTINGS. I unchecked USE SYSTEM PROXY SETTINGS and checked NO PROXY. This change fixed the problem. I also tried checking AUTOPROTECT PROXY SETTING FOR THIS NETWORK and that reinstated the problem. As such I now have NO PROXY checked in that window.

While this is what I had to do on the laptop to get Thunderbird to immediately check for and download message on all 4 addresses the two desktop PCs remain set on USE SYSTEM PROXY SETTINGS and are working as they should. The only difference in overall setup that I can see is that Windows 8 is on the desktops and Windows 8.1 is on the laptop.

However........I don't understand proxy settings and how they affect system security etc. Can someone explain this and let me know if leaving this set at NO PROXY could cause me problems down the road?




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Post Posted April 13th, 2015, 10:27 am

Most people have no need to use a proxy, which is why using a proxy is disabled by default in Thunderbird. A proxy is a server that acts as an intermediary for requests from clients seeking resources from other servers. It might be installed locally or on the network.

If your ISP has you make a connection to a satellite, you are running a VPN, are trying to defeat restrictions based on your geographical location, or have many PCs at the same location with a slow Internet connection you might need a proxy for performance or security reasons. You normally don't need a proxy to run a firewall or other security software such as anti-virus or malware scanner. An office might provide a Internet connection that requires you to make a SOCKS5 connection to a proxy to improve performance by caching repeatably requested web pages. In that case you might have to also configure Thunderbird to use the proxy, even though it only improves performance for browsers.

Its also possible to configure Thunderbird to use a proxy without changing the 'connection settings' in tools -> options . Anti-virus scanners normally can't scan messages received over a SSL connection. One way to work around that is to install a local proxy (provided with your anti-virus scanner) that you configure your account settings to use as the mail server, and configure the proxy to make a SSL connection to the real mail server. AVG supports that for example. The proxy can scan your email since you make a insecure connection to it. This is quite different from what you were talking about since Thunderbird has no idea that it is using a proxy in this case.

Posts: 24
Joined: March 14th, 2014, 3:48 am

Post Posted April 13th, 2015, 1:34 pm

Thank you. That is a much more detailed explanation than I was able to find online.

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