I seem to be receiving some emails on my blackberry but not others.
Probably what is happening is that you have another device like Outlook or another email client on a laptop or desktop somewhere checking your emails periodically as well as your Blackberry which results in your Blackberry only getting some of the emails sent to you.
What is happening is that your PC is downloading your emails from your server mailbox, then your Blackberry is going to check your server mailbox and there is nothing there (because your PC downloaded them already).
To fix this, you need to make two things happen.
note: here we will explain about Outlook as most email clients have similar settings.
1. You need to make sure your Outlook is "storing copies of messages on the server" or just use IMAP. If you are already using IMAP then probably you will not even have this issue we are discussing but if you are using POP setting in your Outlook then probably its not configured correctly to store copies of messages on the server hence the appearance of mails being lost/mislaid.
2. You need to make sure that your blackberry is configured correctly. If you are receiving emails on your blackberry already, then "probably" your blackberry account is already configured correctly but just in case you have doubts, then you should see this link here.
How do I configure Outlook to store messages on the server?
1. Open Outlook
2. From the Tools menu, Select E-mail Accounts.
3. Select View or change existing e-mail Account.
4. Click Next
5. Select your mail account and click Change.
6. Click More Settings
7. On the Advanced tab, under Delivery, check Leave a copy of messages on the server