diff --git a/Modules/Sources/Networking/Model/SiteAPI.swift b/Modules/Sources/Networking/Model/SiteAPI.swift
index cc8acbb75f9..f8d59dc755a 100644
--- a/Modules/Sources/Networking/Model/SiteAPI.swift
+++ b/Modules/Sources/Networking/Model/SiteAPI.swift
@@ -45,7 +45,17 @@ public struct SiteAPI: Decodable, Equatable, GeneratedFakeable {
         }
 
         let siteAPIContainer = try decoder.container(keyedBy: SiteAPIKeys.self)
-        let namespaces = siteAPIContainer.failsafeDecodeIfPresent([String].self, forKey: .namespaces) ?? []
+
+        /// Some third-party plugins (like CoCart API) alter the response of `namespaces` field into a dictionary instead of array.
+        /// This workaround transforms the unexpected dictionary to extract the values in the dictionary.
+        let namespaces = siteAPIContainer.failsafeDecodeIfPresent(
+            targetType: [String].self,
+            forKey: .namespaces,
+            alternativeTypes: [
+                .dictionary(transform: { Array($0.values) })
+            ]
+        ) ?? []
+
         let authentication = try? siteAPIContainer.decode(Authentication.self, forKey: .authentication)
         let applicationPasswordAvailable = authentication?.applicationPasswords?.endpoints?.authorization != nil
 
diff --git a/Modules/Sources/NetworkingCore/Extensions/KeyedDecodingContainer+Woo.swift b/Modules/Sources/NetworkingCore/Extensions/KeyedDecodingContainer+Woo.swift
index 7bce142c4dc..093b2c4467d 100644
--- a/Modules/Sources/NetworkingCore/Extensions/KeyedDecodingContainer+Woo.swift
+++ b/Modules/Sources/NetworkingCore/Extensions/KeyedDecodingContainer+Woo.swift
@@ -6,6 +6,7 @@ public enum AlternativeDecodingType<T> {
     case string(transform: (String) -> T)
     case bool(transform: (Bool) -> T)
     case integer(transform: (Int) -> T)
+    case dictionary(transform: ([String: String]) -> T)
 }
 
 // MARK: - KeyedDecodingContainer: Bulletproof JSON Decoding.
@@ -60,6 +61,10 @@ public extension KeyedDecodingContainer {
                 if let result = failsafeDecodeIfPresent(integerForKey: key) {
                     return transform(result)
                 }
+            case .dictionary(let transform):
+                if let result = failsafeDecodeIfPresent([String: String].self, forKey: key) {
+                    return transform(result)
+                }
             }
         }
         return nil
diff --git a/Modules/Tests/NetworkingTests/Mapper/SiteAPIMapperTests.swift b/Modules/Tests/NetworkingTests/Mapper/SiteAPIMapperTests.swift
index c7373302d1d..4d3ce308b5a 100644
--- a/Modules/Tests/NetworkingTests/Mapper/SiteAPIMapperTests.swift
+++ b/Modules/Tests/NetworkingTests/Mapper/SiteAPIMapperTests.swift
@@ -5,7 +5,7 @@ import XCTest
 
 /// SiteAPIMapperTests Unit Tests
 ///
-class SiteAPIMapperTests: XCTestCase {
+final class SiteAPIMapperTests: XCTestCase {
 
     /// Dummy Site ID.
     ///
@@ -54,6 +54,18 @@ class SiteAPIMapperTests: XCTestCase {
         XCTAssertEqual(apiSettings?.namespaces, dummyBrokenNamespaces)
         XCTAssertEqual(apiSettings?.highestWooVersion, WooAPIVersion.none)
     }
+
+    /// Verifies the SiteSetting fields are parsed correctly.
+    ///
+    func test_SiteSetting_with_malformed_namespaces_fields_are_properly_parsed() {
+        let apiSettings = mapLoadSiteAPIResponseWithMalformedNamespaces()
+
+        XCTAssertNotNil(apiSettings)
+        XCTAssertEqual(apiSettings?.siteID, dummySiteID)
+        XCTAssertNotNil(apiSettings?.namespaces)
+        XCTAssertEqual(apiSettings?.namespaces.sorted(), dummyNamespaces.sorted())
+        XCTAssertEqual(apiSettings?.highestWooVersion, WooAPIVersion.mark3)
+    }
 }
 
 
@@ -88,4 +100,10 @@ private extension SiteAPIMapperTests {
     func mapLoadBrokenSiteAPIResponse() -> SiteAPI? {
         return mapSiteAPIData(from: "site-api-no-woo")
     }
+
+    /// Returns the SiteAPIMapper output with malformed namespaces
+    ///
+    func mapLoadSiteAPIResponseWithMalformedNamespaces() -> SiteAPI? {
+        return mapSiteAPIData(from: "site-api-malformed")
+    }
 }
diff --git a/Modules/Tests/NetworkingTests/Responses/site-api-malformed.json b/Modules/Tests/NetworkingTests/Responses/site-api-malformed.json
new file mode 100644
index 00000000000..c6b4c2d4ab4
--- /dev/null
+++ b/Modules/Tests/NetworkingTests/Responses/site-api-malformed.json
@@ -0,0 +1,23 @@
+{
+  "data": {
+    "namespaces": {
+      "0": "oembed\/1.0",
+      "1": "akismet\/v1",
+      "2": "jetpack\/v4",
+      "3": "wpcom\/v2",
+      "4": "wc\/v1",
+      "5": "wc\/v2",
+      "6": "wc\/v3",
+      "7": "wc-pb\/v3",
+      "8": "wp\/v2"
+    },
+    "authentication": [],
+    "_links": {
+      "help": [
+        {
+          "href": "http:\/\/v2.wp-api.org\/"
+        }
+      ]
+    }
+  }
+}
diff --git a/WooCommerce/Classes/Yosemite/DefaultStoresManager.swift b/WooCommerce/Classes/Yosemite/DefaultStoresManager.swift
index 2f5eb8c814f..a552090ee2a 100644
--- a/WooCommerce/Classes/Yosemite/DefaultStoresManager.swift
+++ b/WooCommerce/Classes/Yosemite/DefaultStoresManager.swift
@@ -166,8 +166,10 @@ class DefaultStoresManager: StoresManager {
 
         if case .wpcom = credentials {
             listenToWPCOMInvalidWPCOMTokenNotification()
+            applicationPasswordGenerationFailureObserver = nil
         } else {
             listenToApplicationPasswordGenerationFailureNotification()
+            invalidWPCOMTokenNotificationObserver = nil
         }
 
         return self
@@ -250,6 +252,7 @@ class DefaultStoresManager: StoresManager {
     @discardableResult
     func deauthenticate() -> StoresManager {
         applicationPasswordGenerationFailureObserver = nil
+        invalidWPCOMTokenNotificationObserver = nil
 
         if isAuthenticated {
             let resetAction = CardPresentPaymentAction.reset