For a detailed list and descriptions of the channels that this sensor can show, see section Channel List.
Sensor in Other Languages
Dutch: IMAP
French: IMAP
German: IMAP
Japanese: IMAP
Portuguese: IMAP
Russian: IMAP
Simplified Chinese: IMAP
Spanish: IMAP
Remarks
This sensor does not support Secure Remote Password (SRP) ciphers.
This sensor does not support Microsoft 365 mailboxes. If you want to monitor a Microsoft 365 mailbox, use the Microsoft 365 Mailbox sensor.
This sensor only supports IPv4.
This sensor has a medium performance impact.
If you use content checks, we recommend that you use a dedicated IMAP account that is only checked by PRTG. Editing mails in the mailbox of the monitored IMAP account can lead to false alarms or malfunctions of this sensor.
This sensor might not work properly when monitoring subfolders of mailboxes. If it has to check subsequent emails with identical subjects, it might not recognize emails that come in later.
Emails that arrive during the Daylight Saving Time (winter time to summer time) change might not be processed properly. If you experience this issue, delete the respective emails.
If the name contains angle brackets (<>), PRTG replaces them with braces ({}) for security reasons. For more information, see the Knowledge Base: What security features does PRTG include?
This setting is for your information only. You cannot change it.
Tags
Enter one or more tags. Confirm each tag with the Spacebar key, a comma, or the Enter key. You can use tags to group objects and use tag-filtered views later on. Tags are not case-sensitive. Tags are automatically inherited.
It is not possible to enter tags with a leading plus (+) or minus (-) sign, nor tags with parentheses (()) or angle brackets (<>).
For performance reasons, it can take some minutes until you can filter for new tags that you added.
The sensor has the following default tags that are automatically predefined in the sensor's settings when you add the sensor:
imapsensor
mailsensor
Priority
Select a priority for the sensor. This setting determines the position of the sensor in lists. The highest priority is at the top of a list. Choose from the lowest priority () to the highest priority ().
Connectivity
Connectivity
Setting
Description
Timeout (Sec.)
Enter a timeout in seconds for the request. Enter an integer. The maximum timeout value is 900 seconds (15 minutes).
If the reply takes longer than this value, the sensor cancels the request and shows a corresponding error message.
Port
Specify the port that the sensor uses for the IMAP connection. The default port for unsecure connections is 143 and the default port for secure connections is 993. The actual setting depends on the server you connect to. Enter an integer.
We recommend that you use the default value.
If the connection is unsuccessful, try a different port number.
Transport-Level Security
Define how the sensor handles the security of the connection:
Use transport-level security if available using StartTLS (default): Try to connect to the server via a Secure Sockets Layer (SSL)/Transport Layer Security (TLS) secured connection and StartTLS. If the server does not support this, the sensor tries to connect without connection security.
Use transport-level security if available: Try to connect to the server via an SSL/TLS-secured connection. If the server does not support this, the sensor tries to connect without connection security.
Enforce transport-level security using StartTLS: Try to connect to the server via an SSL/TLS-secured connection and StartTLS. If the server does not support this, the sensor shows the Downstatus.
Enforce transport-level security: Try to connect to the server via an SSL/TLS-secured connection. If the server does not support this, the sensor shows the Down status.
If the sensor connects to a server via StartTLS, the connection is first established without connection security. After the connection has been established, the sensor sends a certain command (StartTLS) over the unsecured connection to negotiate a secure connection via SSL/TLS.
If the sensor does not use StartTLS, the negotiation of a secure connection happens immediately (implicitly) so that no commands are sent in unencrypted plain text. If no secure connection is possible, no communication takes place.
Sensor Behavior
Sensor Behavior
Setting
Description
Email Processing
Define if the sensor additionally checks the content of all incoming emails:
Do not process emails (default): Only check the availability of the IMAP server and check if a login is successful. Do not process any emails in the IMAP email account.
Count emails in the mailbox: Count the emails in the mailbox.
Process emails in the mailbox: Log in to the IMAP email account and check the emails that it contains. Define further options below.
Result Handling
Define what PRTG does with the sensor result:
Discard result: Do not store the sensor result.
Store result: Store the last sensor result in the \Logs\sensors subfolder of the PRTG data directory on the probe system. The file names are Result of Sensor [ID].txt and Result of Sensor [ID].Data.txt. This setting is for debugging purposes. PRTG overwrites these files with each scanning interval.
This option is not available when the sensor runs on the hosted probe of a PRTG Hosted Monitor instance.
In a cluster, PRTG stores the result in the PRTG data directory of the master node.
Authentication
Authentication
Setting
Description
User Name
Enter a user name for IMAP authentication. Enter a string.
Password
Enter a password for IMAP authentication. Enter a string.
The password must not contain spaces, percent signs (%), or the character combination !*.
Folder Name
Enter the name of a folder in the mailbox (for example, the IMAP folder) that the sensor checks. The default value is Inbox. Unless you set a last message date check below, the sensor always looks at all emails contained in the mailbox.
Make sure that you do not manually edit emails in this mailbox with a different email client because this can result in malfunctions of this sensor's email identification.
Filter Emails in Inbox
This settings section is only visible if you select Process emails in the mailbox.
Filter Emails in Inbox
Setting
Description
Only Include Emails with Matching "From"
Define if you want to check the "From" field of the emails:
Do not check (default): Do not process this field in emails.
Check using simple string search: Process this field in emails using a simple string in plain text.
Check using regular expression: Process this field in emails using a regular expression (regex).
In the search, the sensor scans all emails from the newest to the oldest.
PRTG supports Perl Compatible Regular Expression (PCRE) regex. For more details, see section Regular Expressions.
The sensor finishes the scan with the first match. This means that after it finds a match in one email, the sensor does not perform any further checks in older emails.
Search for
This setting is only visible if you select Check using simple string search or Check using regular expression above.
Enter the email address or the regular expression that the "From" field of the email must contain or match.
Only Include Emails with Matching "Subject"
Define if you want to check the "Subject" field of the emails:
Do not check (default): Do not process this field in emails.
Check using simple string search: Process this field in emails using a simple string in plain text.
Check using regular expression: Process this field in emails using a regular expression (regex).
In the search, the sensor scans all emails from the newest to the oldest.
PRTG supports Perl Compatible Regular Expression (PCRE) regex. For more details, see section Regular Expressions.
The sensor finishes the scan with the first match. This means that after it finds a match in one email, the sensor does not perform any further checks in older emails.
Search for
This setting is only visible if you select Check using simple string search or Check using regular expression above.
Enter the simple string in plain text or the regex that the "Subject" field of the email must contain or match.
Only Include Emails with Matching Email Body
Define if you want to check the body of the emails:
Do not check (default): Do not process the email body.
Check using simple string search: Process the email body using a simple string in plain text.
Check using regular expression: Process the email body using a regex.
In the search, the sensor scans all emails from the newest to the oldest.
PRTG supports Perl Compatible Regular Expression (PCRE) regex. For more details, see section Regular Expressions.
The sensor finishes the scan with the first match. This means that after it finds a match in one email, the sensor does not perform any further checks in older emails.
Search for
This setting is only visible if you select Check using simple string search or Check using regular expression above.
Enter the simple string in plain text or the regex that the body of the email must contain or match.
Only Include Recent Emails
Define if you want to check all emails in the mailbox or only mails that were received during the last few hours:
Do not check message age (default): Check all emails that the mailbox contains.
Emails must be younger than: Only check emails that were received during the last few hours. Define below.
Maximum Age (Hours)
This setting is only visible if you select Emails must be younger than above.
Enter the maximum age in hours. The sensor only processes emails that are younger. Enter an integer.
If No Email Matches the Above Filters
Define which status the sensor shows if it does not find any email in the mailbox that matches the above filters:
Set sensor to up status (default): Show the Up status if the sensor does not find any email in the mailbox that matches the filters.
Set sensor to warning status: Show the Warning status if the sensor does not find any email in the mailbox that matches the filters.
Set sensor to down status: Show the Down status if the sensor does not find any email in the mailbox that matches the filters.
Message
This setting is only visible if you select Set sensor to warning status or Set sensor to down status above.
Define the message that the sensor shows if it does not find any matching emails.
Validate Latest Email
This settings section is only visible if you select Process emails in the mailbox.
The sensor only validates the latest email that matches the above filters. If the sensor does not find a matching email, it does not perform any email validation.
Validate Latest Email
Setting
Description
Set Sensor to Warning Status
Define in which cases the sensor shows the Warning status:
Never (default): Never show the Warning status because of email content.
Always: Always show the Warning status if it could identify any emails.
If subject contains: Show the Warning status if the subject of the email contains the Search String you define below.
If subject does not contain: Show the Warning status if the subject of the email does not contain the Search String you define below.
If email body contains: Show the Warning status if the body of the email contains the Search String you define below.
If email body does not contain: Show the Warning status if the body of the email does not contain the Search String you define below.
Search Method
This setting is only visible if you select If subject contains, If subject does not contain, If email body contains, or If email body does not contain above.
Define the method with which you want to search for the respective condition:
Simple string search: Search the email subject or body with a simple string in plain text.
The characters * and ? work as placeholders. * stands for no number or any number of characters and ? stands for exactly one character. You cannot change this behavior. The literal search for these characters is only possible with a regex.
Regular expression: Search the email subject or body with a regex.
PRTG supports Perl Compatible Regular Expression (PCRE) regex. For more details, see section Regular Expressions.
Search String
This setting is only visible if you select If subject contains, If subject does not contain, If email body contains, or If email body does not contain above.
Define the string that you want to search the email subject or body for. You can enter a simple string in plain text or a regex.
Warning Message
This setting is only visible if you select a "warning" condition above.
Define the message that the sensor shows for the Warning status.
Set Sensor to Down Status
Define in which cases the sensor shows the Down status.
Never (default): Never show the Down status based on email content.
Always: Always show the Down status if any emails could be identified.
If subject contains: Show the Down status if the subject of the found email contains the Search String you define below.
If subject does not contain: Show the Down status if the subject of the found email does not contain the Search String you define below.
If email body contains: Show the Down status if the body of the found email contains the Search String you define below.
If email body does not contain: Show the Down status if the body of the found email does not contain the Search String you define below.
Search Method
This setting is only visible if you select If subject contains, If subject does not contain, If email body contains, or If email body does not contain above.
Define the method with which you want to search for the respective condition:
Simple string search: Search the email subject or body with a simple string in plain text.
The characters * and ? work as placeholders. * stands for no number or any number of characters and ? stands for exactly one character. You cannot change this behavior. The literal search for these characters is only possible with a regex.
Regular expression: Search the email subject or body with a regex.
PRTG supports Perl Compatible Regular Expression (PCRE) regex. For more details, see section Regular Expressions.
Search String
This setting is only visible if you select If subject contains, If subject does not contain, If email body contains, or If email body does not contain above.
Define the string that you want to search the email subject or body for. You can enter a simple string in plain text or a regex.
Error Message
This setting is only visible if you select Always, If subject contains, If subject does not contain, If email body contains, or If email body does not contain above.
Define the message that the sensor shows for the Down status.
Based on Message Age, Set Sensor to Warning Status
Define if you want to check the age of the latest matching email in the mailbox:
Never (default): Do not check the age of the email.
If email is older than: Set the sensor to the Warning status if the found email is older than you define below.
Message Age (Hours)
This setting is only visible if you select the message age check above.
Enter the maximum age in hours. If the processed email is older, the sensor shows the Warning status. Enter an integer.
Make sure you do not manually edit emails in this mailbox with a different email client because this can result in malfunctions of the message age check.
Sensor Display
Sensor Display
Setting
Description
Primary Channel
Select a channel from the list to define it as the primary channel. In the device tree, the last value of the primary channel is always displayed below the sensor's name. The available options depend on what channels are available for this sensor.
You can set a different primary channel later by clicking below a channel gauge on the sensor's Overview tab.
Graph Type
Define how different channels are shown for this sensor:
Show channels independently (default): Show a graph for each channel.
Stack channels on top of each other: Stack channels on top of each other to create a multi-channel graph. This generates a graph that visualizes the different components of your total traffic. You cannot use this option in combination with manual Vertical Axis Scaling (available in the channel settings).
Stack Unit
This setting is only visible if you select Stack channels on top of each other above.
Select a unit from the list. All channels with this unit are stacked on top of each other. By default, you cannot exclude single channels from stacking if they use the selected unit. However, there is an advanced procedure to do so.
Inherited Settings
By default, all of these settings are inherited from objects that are higher in the hierarchy. We recommend that you change them centrally in the root group settings if necessary. To change a setting for this object only, click under the corresponding setting name to disable the inheritance and to display its options.
For more information, see section Root Group Settings, section Scanning Interval.
Schedules, Dependencies, and Maintenance Window
You cannot interrupt the inheritance for schedules, dependencies, and maintenance windows. The corresponding settings from the parent objects are always active. However, you can define additional schedules, dependencies, and maintenance windows. They are active at the same time as the parent objects' settings.
Schedules, Dependencies, and Maintenance Window
For more information, see section Root Group Settings, section Schedules, Dependencies, and Maintenance Window.
Access Rights
Access Rights
For more information, see section Root Group Settings, section Access Rights.
Channel List
Which channels the sensor actually shows might depend on the target device, the available components, and the sensor setup.
Channel
Description
Available
The response time
This channel is the primary channel by default.
Downtime
In the channel table on the Overview tab, this channel never shows any values. PRTG uses this channel in graphs and reports to show the amount of time in which the sensor was in the Down status
Mailbox Size
The number of emails in the defined mailbox
More
KNOWLEDGE BASE
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