EWS callback failed

[ErikBoSo]

Diagnostics

User Agent = Mozilla/5.0 (Linux; Android 14; SM-G998B Build/UP1A.231005.007; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/134.0.6998.39 Mobile Safari/537.36
Requirement set = 1.5
ui = new-mobile
Last Update = Fri, 14 Mar 2025 21:44:02 GMT
mhaVersion = e6ed5b82
contentLanguage = en-DK
displayLanguage = en-DK
hostname = OutlookAndroid
hostVersion = 4.2509.0.0
permissionLevel = 3
canUseAPI = false
canUseRest = true
sufficientPermission = true
origin = https://mha.azurewebsites.net
path = /Pages/uitoggle.html
API used = Not set
itemId = true
itemType = message
itemClass = IPM.Note
noAPIreason = requirements too low
callbackTokenFailure = {"status":"failed","error":{"name":"Internal Error","message":"Internal Error","code":5001}}
ERROR: API failed, trying REST
ERROR: No access token?
ERROR: REST failed, trying EWS
ERROR: EWS callback failed : Failed to retrieve headers.
l.callbackEws (webpack://mha/src/Scripts/ui/getHeaders/GetHeadersEWS.ts:90:22)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:191082)
e (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:113949)
a.agaveHostCallback (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:111761)
Object.g [as agaveHostCallback] (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:110632)
a.ReceiveMessage (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:117159)
agaveHostCallback (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:117536)
ERROR: Unable to obtain callback token.
Fallback to EWS.
{
"status": "failed",
"error": {
"name": "Internal Error",
"message": "Internal Error",
"code": 5001
}
} : Internal Error
_generateError (webpack://mha/node_modules/stacktrace-js/stacktrace.js:28:18)
get (webpack://mha/node_modules/stacktrace-js/stacktrace.js:77:22)
Errors.isError (webpack://mha/src/Scripts/stacks.ts:28:26)
handler (webpack://mha/src/Scripts/stacks.ts:45:13)
parse (webpack://mha/src/Scripts/Errors.ts:81:14)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:191082)
e (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:113949)
ERROR: Async Response
{
"status": "succeeded"
}
_generateError (webpack://mha/node_modules/stacktrace-js/stacktrace.js:28:18)
get (webpack://mha/node_modules/stacktrace-js/stacktrace.js:77:22)
Errors.isError (webpack://mha/src/Scripts/stacks.ts:28:26)
handler (webpack://mha/src/Scripts/stacks.ts:45:13)
parse (webpack://mha/src/Scripts/Errors.ts:81:14)
log (webpack://mha/src/Scripts/ui/getHeaders/GetHeadersEWS.ts:95:23)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-android-16.00.js:20:191082)
OK

[jtermine]

Same problem. Nearly verbatim.

[alittle158]

Same problem as well on mobile (Outlook for iOS/iPadOS), but desktop and web Outlook seem to be fine most of the time.

[shawn-saucier-genlp-com]

Same problem as well on mobile (Outlook for iOS), but desktop and web Outlook seem to be fine most of the time.
Have uninstalled and reinstalled, no change.

Also, I believe MS is getting rid of EWS on O365. Is there a plan for that?

User Agent = Mozilla/5.0 (iPhone; CPU iPhone OS 18_7 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Mobile/15E148
Requirement set = 1.11
ui = new-mobile
Last Update = Wed, 14 Jan 2026 15:34:33 GMT
mhaVersion = 1e7192e0
contentLanguage = en-US
displayLanguage = en-US
hostname = OutlookIOS
hostVersion = 5.2601.0.0
permissionLevel = 3
canUseAPI = true
canUseRest = true
sufficientPermission = true
origin = https://mha.azurewebsites.net/
path = /Pages/uitoggle.html
API used = Not set
itemId = true
itemType = message
itemClass = IPM.Note
getAllInternetHeadersAsyncFailure = {"status":"failed","error":{"name":"Permission Denied","message":"You don't have sufficient permissions for this action.","code":7000}}
callbackTokenFailure = {"status":"failed","error":{"name":"AccessRestricted","message":"Internal protocol error: '-2147467259'.","code":9017},"diagnostics":{"InvokeCodeResult":-2147467259}}
ERROR: API failed, trying REST
ERROR: getAllInternetHeadersAsync failed.
Fallback to Rest.
{
"status": "failed",
"error": {
"name": "Permission Denied",
"message": "You don't have sufficient permissions for this action.",
"code": 7000
}
} : You don't have sufficient permissions for this action.
_generateError (webpack://mha/node_modules/stacktrace-js/stacktrace.js:28:18)
get (webpack://mha/node_modules/stacktrace-js/stacktrace.js:77:22)
Errors.isError (webpack://mha/src/Scripts/stacks.ts:28:41)
handler (webpack://mha/src/Scripts/stacks.ts:36:11)
handler (webpack://mha/src/Scripts/stacks.ts:45:31)
error (webpack://mha/src/Scripts/Errors.ts:81:20)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:204184)
d (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:116009)
b (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:111387)
::
::
ERROR: No access token?
ERROR: REST failed, trying EWS
ERROR: Unable to obtain callback token.
Fallback to EWS.
{
"status": "failed",
"error": {
"name": "AccessRestricted",
"message": "Internal protocol error: '-2147467259'.",
"code": 9017
},
"diagnostics": {
"InvokeCodeResult": -2147467259
}
} : Internal protocol error: '-2147467259'.
_generateError (webpack://mha/node_modules/stacktrace-js/stacktrace.js:28:18)
get (webpack://mha/node_modules/stacktrace-js/stacktrace.js:77:22)
Errors.isError (webpack://mha/src/Scripts/stacks.ts:28:41)
handler (webpack://mha/src/Scripts/stacks.ts:36:11)
handler (webpack://mha/src/Scripts/stacks.ts:45:31)
error (webpack://mha/src/Scripts/Errors.ts:81:20)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:204184)
d (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:116009)
b (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:111387)
::
::
ERROR: Async Response
{
"status": "succeeded"
}
_generateError (webpack://mha/node_modules/stacktrace-js/stacktrace.js:28:18)
get (webpack://mha/node_modules/stacktrace-js/stacktrace.js:77:22)
Errors.isError (webpack://mha/src/Scripts/stacks.ts:28:41)
handler (webpack://mha/src/Scripts/stacks.ts:36:11)
handler (webpack://mha/src/Scripts/stacks.ts:45:31)
error (webpack://mha/src/Scripts/Errors.ts:81:20)
asyncResult (webpack://mha/src/Scripts/ui/getHeaders/GetHeadersEWS.ts:93:27)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:204184)
d (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:116009)
b (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:111387)
::
::
ERROR: EWS callback failed : Failed to retrieve headers.
mhaStrings (webpack://mha/src/Scripts/ui/getHeaders/GetHeadersEWS.ts:88:32)
a (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:204184)
d (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:116009)
b (https://appsforoffice.microsoft.com/lib/1/hosted/outlook-ios-16.00.js:20:111387)
::
::