1.1.1 Check if Outlook is offline, or network disconnect

1.1.2 Check if the mailbox is full

1.1.3 Check if user domain ID is locked

1.1.4 Check if there is any rule block or redirect email to non-inbox folder

1.1.5 Check if it is related to POP3 account issues

1.1.6 Check if it is PST file related issues

1.1.7 Check if the sender can reproduce the problem

1.1.8 Escalate to SSR for log tracking

1.2.1 Check if Outlook is offline, or network disconnect

1.2.2 Check if the mailbox is full

1.2.3 Check if user domain ID is locked

1.2.4 Check if the sender email has been blocked by email anti spam server (size, attachment)

1.2.5 Check if there is any rule block or redirect email to non-inbox folder

1.2.6 Check if it is related to POP3 account issues

1.2.7 Check if the user can still receive email from other public internal email, e.g. Gmail

1.2.8 Check if the sender can reproduce the problem

1.2.9 Escalate to SSR for log tracking

2.1.1 Check if Outlook is offline, or network disconnect

2.1.2 Check if the mailbox is full (sender and recipients)

2.1.3 Check if user domain ID is locked

2.1.4 Check if the cached email address in Outlook is outdated

2.1.5 Check if the email is oversize or contains harmful attachment

2.1.6 Check if it is related to POP3 account issues

2.1.7 Escalate to SSR for log tracking

2.2.1 Check if Outlook is offline, or network disconnect

2.2.2 Check if the mailbox is full (sender and recipients)

2.2.3 Check if user domain ID is locked

2.2.4 Check if the email is oversize or contains harmful attachment

2.2.5 Check if it is related to POP3 account issues

2.2.6 Check if the user can still send email from other public internal email, e.g. Gmail

2.2.7 Escalate to SSR for log tracking

3.1.1 Escalate via TT, ask NSC to check if network utilization is normal

3.1.2 Ask NSC to check if issue related to Riverbed caching server via TT

3.2.1 Check if Cached Exchange model is enabled

3.2.2 Check if it is OST file problem

3.2.3 Check if it is client side rules problem

3.2.4 Check if it is Outlook Addon problem

3.2.5 Check if there is any specific email download causing issue

3.2.6 Escalate to DSM for further escalation