Message Headers with Failed SPF Check and SCL=5

For example:

Case 1. Email from microsoft.com to contoso.com

Authentication-Results: spf=fail (sender IP is 23.1.4.9)
smtp.mailfrom=microsoft.com; contoso.mail.onmicrosoft.com;
dkim=none (message not signed) header.d=none;
Received-SPF: Fail (protection.outlook.com: domain of microsoft.com does not
designate 23.1.4.9 as permitted sender) receiver=protection.outlook.com;
client-ip=23.1.4.9; helo=exchange2010.contoso.com;
X-MS-Exchange-Organization-SCL: 5
X-Forefront-Antispam-Report: CIP:23.1.4.9;CTRY:HK;IPV:CAL;IPV:NLI;EFV:NLI;SFV:SPM;
SFS:(2980300002)(339900001)(489007)(189002)(252514010)(199003)(3905003)(5003600100002)
(450100001)(33646002)(86362001)(69596002)(66066001)(84326002)(46102003)(81156007)
(19300405004)(6806004)(26826002)(67866002)(92566002)(17760045003)(85426001)(86146001)
(18206015028)(19580395003)(19625215002)(62966003)(64706001)(24736003)(10290500002)
(19580405001)(106116001)(99936001)(50986999)(107886002)(10400500002)(86612001)
(5005710100001)(77156002)(15843345004)(105606002)(19618635001)(108616004)(189998001)
(16236675004)(87936001)(16234385003)(5001960100002)(10090500001)(19627595001)(76176999)
(15975445007)(106466001)(4001540100001)(19617315012)(54356999)(66926002)(575784001)
(2900100001)(5001830100001)(5001860100001)(512914005)(2950100001)(102836002)(2656002)
(110136002)(82516004);DIR:INB;SFP:;SCL:5;SRVR:SG2PR0301MB1285;H:exchange2010.contoso.com;
FPR:;SPF:Fail;PTR:009.4.1.23.static.isp.com;MX:1;A:1;LANG:en;

Case 2. Email from hp.com to contoso.com

Authentication-Results: spf=none (sender IP is 23.1.4.9) smtp.mailfrom=hp.com; contoso.mail.onmicrosoft.com; dkim=none (message not
signed) header.d=none;
Received-SPF: None (protection.outlook.com: hp.com does not designate  permitted sender hosts)
X-MS-Exchange-Organization-SCL: 5
X-Forefront-Antispam-Report: CIP:23.1.4.9;CTRY:HK;IPV:NLI;EFV:NLI;SFV:SPM;SFS:(6009001)
(2980300002)(428002)(53754006)(377454003)(189002)(6602003)(199003)(66066001)(64706001)
(86362001)(2656002)(24736003)(5001860100001)(5250100002)(2900100001)(87936001)(5001960100002)
(81156007)(5001830100001)(4001540100001)(110136002)(189998001)(101416001)(69596002)(512954002)
(105586002)(106466001)(102836002)(15975445007)(50986999)(77156002)(19300405004)(450100001)
(54356999)(62966003)(84326002)(16236675004)(6806004)(108616004)(92566002)(5003600100002)
(19580395003)(46102003)(33646002)(19625215002)(19580405001)(82516004);DIR:INB;SFP:;SCL:5;
SRVR:TY1PR0301MB1120;H:exchange2010.contoso.com;FPR:;SPF:None;PTR:009.4.1.23.static.isp.com;MX:1;A:1;LANG:en;

Case 3. Email from gmail.com contoso.com

Authentication-Results: spf=softfail (sender IP is 23.1.4.9)
smtp.mailfrom=gmail.com; contoso.mail.onmicrosoft.com;
dkim=fail (signature did not verify) header.d=gmail.com;
Received-SPF: SoftFail (protection.outlook.com: domain of transitioning
gmail.com discourages use of 23.1.4.9 as permitted sender)
X-MS-Exchange-Organization-SCL: 5
X-Forefront-Antispam-Report: CIP:23.1.4.9;CTRY:HK;IPV:CAL;IPV:NLI;EFV:NLI;SFV:SPM;
SFS:(6009001)(2980300002)(199003)(189002)(189998001)(73392002)(97736004)(4001540100001)
(64706001)(76482005)(105596002)(83322999)(106466001)(81156007)(5001860100001)(5001960100002)
(68736005)(5000100001)(62966003)(564344004)(107886002)(5001830100001)(42186005)(82202001)
(92566002)(450100001)(2351001)(55446002)(229853001)(54356999)(46102003)(63696999)(87572001)
(956001)(110136002)(50986999)(81442002)(87936001)(61266001)(86362001)(69596002)(77156002)
(73972006)(26826002)(512874002)(6806004)(84326002)(59536001)(82516004);DIR:INB;SFP:;SCL:5;
SRVR:SG2PR0301MB1287;H:exchange2010.contoso.com;FPR:;SPF:SoftFail;PTR:ErrorRetry;A:1;MX:1;LANG:en;