Web service callout failed: Unexpected element / Read Timed Out / IO Exception

[Anonymous]

We have integrated Salesforce with Marketo for sending outbound emails.  It was working fine for the past two months and recetly we started getting the following error message when we try to send emails from Salesforce:

1.  Web service callout failed: Unexpected element. Parser was expecting element 'http://schemas.xmlsoap.org/soap/envelope/:Envelope​' but found ':HTML'

2. IO Exception: Connection Reset error

3. IO Exception: Read Timed Out

I have submitted a ticket with both Salesforce and Marketo.  The Marketo Flag Sync is set for most of the customers, sometimes we set it on the fly when the user clicks the Send Email button and not sure this is timing related issue.

Any of you have seen this error before?  Please let me know if you have any suggestions or thoughts on this.

Thanks in advance for your help.

Thanks,
Venkat
Email: venkataramananb@gmail.com

[Anonymous]

Venkat,
Webhooks wait 30 seconds to get a response.  It looks like the WH did not receive a reply within this time window.  Is the WH calling an SFDC API?

Raj

[Anonymous]

We are using SFDC API.    This is the reponse I got from Salesforce regarding WebService Call Out error:
"The message you are getting is because an error is generated as Saleforce is trying to parse the response is and it isn't logged unfortunately.

The parsing error is happening because instead of a SOAP message response you are getting an HTML page. This usually happens when you are accessing a service that is protected behind a firewall. Which means you may be able to see the service when browsing on your computer but remember that Salesforce is outside of your firewall and thus any communication by Salesforce to your service will be blocked"

In our case, it cannot be a firewall issue.  This is working fine 95% of the time. Not sure this is related to network or sync timing on Marketo. 

[Anonymous]

Please provide your subscription details (munchkin Account Id) and I'll take a look