System Limitations

The following list represents the most important limitations in the InterFAX system. Other limitations may apply, but will usually not have an impact on users. Please note that this list may change over time.

For any specific questions, please contact Support.

Outbound Service

Maximum number of pages per fax: 100 pages (more can be accommodated by special request).
Maximum number of email-to-fax recipients (total addresses in "To:" and "Cc:" lines): 500
Maximum number of recipients in a single submission (faxing via lists or submission via Web Service): 20,000
Maximum total filesize of fax attachments: 20MB
Maximum total filesize of fax attachments, where the email is electronically signed: 10MB
Fax images are stored and visible for: 14 days.
For prepaid users: Fax information is kept for 30 days after the prepaid card that was used at the time has been depleted.
For invoiced users: Fax information is kept for 30 days after the end of the month during which the fax was sent.
Maximum postpone time: 30 days.
No support for password-protected files.
No support for read-only files (which bring up a pop-up when opened)
Macros are disabled. Do not use macros in case they affect document output.
Supported attachment file types: See complete list at Supported File Types.
Charset 'Windows-31J' is currently not supported by Windows, as a result it is not supported by InterFAX. As an alternative, please use Charset 'shift_jis' instead. For more information, please see the article - here.
Maximum number of file attachments in Secure “Send Fax” and “Send Merge”: 5
Maximum frequency of polling for fax status: up to 6 requests per minute.

Inbound Service

The account manager may define up to 10 shared properties.
Maximum number of forwarding addresses: 25 addresses.
Maximum allowed time between page breaks: 600 seconds.
The user may download fax image/s in the following formats: PDF, TIF, PNG.
Users can store received messages and view them for 12 months. Extended storage period is available, please visit our Prices page for additional details.
Maximum frequency of polling for fax status: up to 6 requests per minute.

SOAP Web Service

Maximum request size of any type: 8 MB.
Maximum file size when using partial upload: 20 MB.
Maximum frequency of polling for fax status: up to 6 requests per minute.
Maximum number of items returned in the following methods: (for outbound faxes) FaxStatus, FaxStatusEx, FaxQuery, FaxQuery2 and (for inbound faxes) GetList, GetList2: 100 items.
However, when querying by verb Parent in the FaxQuery and FaxQuery2 methods (that is, when retrieving transactions in a broadcast): 20,000 items.
Maximum chunk size when using GetImageChunk download (of inbound faxes): 4 MB.

REST Web Service

Maximum request size of any type: 8 MB.
Maximum frequency of polling for fax status: up to 6 requests per minute.
Maximum number of items returned in the following methods: (for outbound faxes) Faxes, Completed and (for inbound faxes) GetList: 25 items.

Online Control Panel