You can connect to an IMAP server as often as you want, BUT... you may be restricted in the number of simultaneous channels that are open during that connection.

If you use an apple device for getting mail eg: ipad, turn it off. They have no limit in the number connections they will use, which makes sharing difficult.

This is the standard location and method of access: Right click on the Imap mail account in Folder Pane and select 'Settings'. Select : 'Server Settings' for that imap mail account. Click on 'Advanced...' button 'Maximum number of server connections to cache XX' Suggest you lower the number. click on 'OK'

click on 'OK'

I've included an image below...it highlights 'show only subscribed folders' - used for another query :) but it is the same location.

More info:

• http://kb.mozillazine.org/IMAP:_advanced_account_configuration

You say there is no 'Advanced' button..post an image showing the issue. What version of Thunderbird are you using ? What OS are you using?

Thanks for the reply. 45.5.0 on Windows 10. I've followed those instructions previously and again now, still no 'Advanced' button. Screenshot attached.

Your screenshot indicates you may have set up the account twice, one for POP (top), one for IMAP (below that). The maximum number of connections exceeded error message should occur for IMAP servers only, and hence the fix applies to IMAP settings.

Both accounts have an Advanced... button in Server Settings, but make sure to choose the bottom one for the IMAP account as displayed in Toad-Hall’s screenshot. (You can see that screenshot has POP account settings above it as well, similar to your settings.)

I’m not entirely sure, but do actively use the account in both setups, i.e. do you receive email in both folders? Perhaps that may cause the issue since even though you are connecting to 2 separate servers, they are simultaneous connections in some way. Switching off the POP account may therefore be a good thing, as well as resolve the issue if lowering the number as suggested above does not help.

Ah! What your seeing is a gmail account with a similar title as opposed to a .com address where the problem is. Many thanks

Very well, but in that case the error message is not about the Maximum number of server connections to cache error message from Thunderbird as assumed above, but a message from the ISP.

If you tell who the ISP is, we may be able to find a solution.

ISP is Bluehost

Since the error message is IMAP specific nevertheless, I tend to think you are either seeing a message for the Gmail account set up for IMAP (or another IMAP configured account below the ones visible in the screenshot), or there may be another device set up for Bluehost using IMAP, such as a phone, though it would be rare to see the error appear in Thunderbird. POP servers can not use simultaneous connections, and Thunderbird should not try to access them this way.

See this help page.

Where and exactly when do you see the error message? Can you post a screenshot? And are you 100% sure it pops up when fetching email using the POP account in Thunderbird for Bluehost only? You can use the small arrow on the right side of the Get Messages button to find out.

You can also open the Error Console using the Tools menu and look for more specific info on the error. Perhaps you could post that info here?

Thanks for all your help, it's much appreciated. I ran a few virus checks as there were a couple of other behaviour issues on the machine. Nothing was reported until I ran Avira which reported a number of detections and cleaned them. So at present Thunderbird is behaving, I've done this before and then within 48 hrs it starts again. I'm hoping this time it is sorted, I'll let you know. Thanks once again.