diff --git a/services/real-time/app/js/Router.js b/services/real-time/app/js/Router.js
index ec6de5136f..1aae3ea64e 100644
--- a/services/real-time/app/js/Router.js
+++ b/services/real-time/app/js/Router.js
@@ -33,6 +33,7 @@ module.exports = Router = {
     }
     attrs.client_id = client.id
     attrs.err = error
+    attrs.method = method
     if (error.name === 'CodedError') {
       logger.warn(attrs, error.message)
       const serializedError = { message: error.message, code: error.info.code }
diff --git a/services/real-time/app/js/WebApiManager.js b/services/real-time/app/js/WebApiManager.js
index 71cba0d526..403de53cfe 100644
--- a/services/real-time/app/js/WebApiManager.js
+++ b/services/real-time/app/js/WebApiManager.js
@@ -8,6 +8,7 @@ const logger = require('logger-sharelatex')
 const {
   CodedError,
   CorruptedJoinProjectResponseError,
+  NotAuthorizedError,
   WebApiRequestFailedError
 } = require('./Errors')
 
@@ -55,6 +56,10 @@ module.exports = {
               'TooManyRequests'
             )
           )
+        } else if (response.statusCode === 403) {
+          callback(new NotAuthorizedError())
+        } else if (response.statusCode === 404) {
+          callback(new CodedError('project not found', 'ProjectNotFound'))
         } else {
           callback(new WebApiRequestFailedError(response.statusCode))
         }
diff --git a/services/real-time/app/js/WebsocketController.js b/services/real-time/app/js/WebsocketController.js
index a7b2cd43fa..89066a9661 100644
--- a/services/real-time/app/js/WebsocketController.js
+++ b/services/real-time/app/js/WebsocketController.js
@@ -356,7 +356,7 @@ module.exports = WebsocketController = {
       cursorData.doc_id,
       function (error) {
         if (error) {
-          logger.warn(
+          logger.info(
             { err: error, client_id: client.id, project_id, user_id },
             "silently ignoring unauthorized updateClientPosition. Client likely hasn't called joinProject yet."
           )
diff --git a/services/real-time/test/acceptance/js/JoinProjectTests.js b/services/real-time/test/acceptance/js/JoinProjectTests.js
index 051c33d0c7..508e2b6614 100644
--- a/services/real-time/test/acceptance/js/JoinProjectTests.js
+++ b/services/real-time/test/acceptance/js/JoinProjectTests.js
@@ -176,6 +176,128 @@ describe('joinProject', function () {
     })
   })
 
+  describe('when not authorized and web replies with a 403', function () {
+    before(function (done) {
+      return async.series(
+        [
+          (cb) => {
+            return FixturesManager.setUpProject(
+              {
+                project_id: 'forbidden',
+                privilegeLevel: 'owner',
+                project: {
+                  name: 'Test Project'
+                }
+              },
+              (e, { project_id, user_id }) => {
+                this.project_id = project_id
+                this.user_id = user_id
+                cb(e)
+              }
+            )
+          },
+
+          (cb) => {
+            this.client = RealTimeClient.connect()
+            this.client.on('connectionAccepted', cb)
+          },
+
+          (cb) => {
+            this.client.emit(
+              'joinProject',
+              { project_id: this.project_id },
+              (error, project, privilegeLevel, protocolVersion) => {
+                this.error = error
+                this.project = project
+                this.privilegeLevel = privilegeLevel
+                this.protocolVersion = protocolVersion
+                cb()
+              }
+            )
+          }
+        ],
+        done
+      )
+    })
+
+    it('should return an error', function () {
+      this.error.message.should.equal('not authorized')
+    })
+
+    it('should not have joined the project room', function (done) {
+      RealTimeClient.getConnectedClient(
+        this.client.socket.sessionid,
+        (error, client) => {
+          expect(Array.from(client.rooms).includes(this.project_id)).to.equal(
+            false
+          )
+          done()
+        }
+      )
+    })
+  })
+
+  describe('when deleted and web replies with a 404', function () {
+    before(function (done) {
+      return async.series(
+        [
+          (cb) => {
+            return FixturesManager.setUpProject(
+              {
+                project_id: 'not-found',
+                privilegeLevel: 'owner',
+                project: {
+                  name: 'Test Project'
+                }
+              },
+              (e, { project_id, user_id }) => {
+                this.project_id = project_id
+                this.user_id = user_id
+                cb(e)
+              }
+            )
+          },
+
+          (cb) => {
+            this.client = RealTimeClient.connect()
+            this.client.on('connectionAccepted', cb)
+          },
+
+          (cb) => {
+            this.client.emit(
+              'joinProject',
+              { project_id: this.project_id },
+              (error, project, privilegeLevel, protocolVersion) => {
+                this.error = error
+                this.project = project
+                this.privilegeLevel = privilegeLevel
+                this.protocolVersion = protocolVersion
+                cb()
+              }
+            )
+          }
+        ],
+        done
+      )
+    })
+
+    it('should return an error', function () {
+      this.error.code.should.equal('ProjectNotFound')
+    })
+
+    it('should not have joined the project room', function (done) {
+      RealTimeClient.getConnectedClient(
+        this.client.socket.sessionid,
+        (error, client) => {
+          expect(Array.from(client.rooms).includes(this.project_id)).to.equal(
+            false
+          )
+          done()
+        }
+      )
+    })
+  })
+
   return describe('when over rate limit', function () {
     before(function (done) {
       return async.series(
diff --git a/services/real-time/test/acceptance/js/helpers/MockWebServer.js b/services/real-time/test/acceptance/js/helpers/MockWebServer.js
index a2cf5af50b..2de9e61275 100644
--- a/services/real-time/test/acceptance/js/helpers/MockWebServer.js
+++ b/services/real-time/test/acceptance/js/helpers/MockWebServer.js
@@ -38,6 +38,12 @@ module.exports = MockWebServer = {
   joinProjectRequest(req, res, next) {
     const { project_id } = req.params
     const { user_id } = req.query
+    if (project_id === 'not-found') {
+      return res.status(404).send()
+    }
+    if (project_id === 'forbidden') {
+      return res.status(403).send()
+    }
     if (project_id === 'rate-limited') {
       return res.status(429).send()
     } else {
diff --git a/services/real-time/test/unit/js/WebApiManagerTests.js b/services/real-time/test/unit/js/WebApiManagerTests.js
index 4435bc14f9..a366a2e75d 100644
--- a/services/real-time/test/unit/js/WebApiManagerTests.js
+++ b/services/real-time/test/unit/js/WebApiManagerTests.js
@@ -91,6 +91,53 @@ describe('WebApiManager', function () {
       })
     })
 
+    describe('when web replies with a 403', function () {
+      beforeEach(function () {
+        this.request.post = sinon
+          .stub()
+          .callsArgWith(1, null, { statusCode: 403 }, null)
+        this.WebApiManager.joinProject(
+          this.project_id,
+          this.user_id,
+          this.callback
+        )
+      })
+
+      it('should call the callback with an error', function () {
+        this.callback
+          .calledWith(
+            sinon.match({
+              message: 'not authorized'
+            })
+          )
+          .should.equal(true)
+      })
+    })
+
+    describe('when web replies with a 404', function () {
+      beforeEach(function () {
+        this.request.post = sinon
+          .stub()
+          .callsArgWith(1, null, { statusCode: 404 }, null)
+        this.WebApiManager.joinProject(
+          this.project_id,
+          this.user_id,
+          this.callback
+        )
+      })
+
+      it('should call the callback with an error', function () {
+        this.callback
+          .calledWith(
+            sinon.match({
+              message: 'project not found',
+              info: { code: 'ProjectNotFound' }
+            })
+          )
+          .should.equal(true)
+      })
+    })
+
     describe('with an error from web', function () {
       beforeEach(function () {
         this.request.post = sinon