diff --git a/src/components/structures/RoomView.js b/src/components/structures/RoomView.js
index 01485deecbd..4866fe3f601 100644
--- a/src/components/structures/RoomView.js
+++ b/src/components/structures/RoomView.js
@@ -26,6 +26,7 @@ const React = require("react");
 const ReactDOM = require("react-dom");
 import PropTypes from 'prop-types';
 import Promise from 'bluebird';
+import filesize from 'filesize';
 const classNames = require("classnames");
 import { _t } from '../../languageHandler';
 
@@ -49,8 +50,6 @@ import SettingsStore, {SettingLevel} from "../../settings/SettingsStore";
 const DEBUG = false;
 let debuglog = function() {};
 
-let mediaLimitCache = null;
-
 const BROWSER_SUPPORTS_SANDBOX = 'sandbox' in document.createElement('iframe');
 
 if (DEBUG) {
@@ -96,9 +95,9 @@ module.exports = React.createClass({
             roomLoading: true,
             peekLoading: false,
             shouldPeek: true,
-            
-            // Media limits for uploading, this may change.
-            mediaLimits: {},
+
+            // Media limits for uploading.
+            mediaConfig: undefined,
 
             // The event to be scrolled to initially
             initialEventId: null,
@@ -152,24 +151,31 @@ module.exports = React.createClass({
         MatrixClientPeg.get().on("RoomState.members", this.onRoomStateMember);
         MatrixClientPeg.get().on("RoomMember.membership", this.onRoomMemberMembership);
         MatrixClientPeg.get().on("accountData", this.onAccountData);
-        this._fetchMediaLimits();
+        this._fetchMediaConfig();
         // Start listening for RoomViewStore updates
         this._roomStoreToken = RoomViewStore.addListener(this._onRoomViewStoreUpdate);
         this._onRoomViewStoreUpdate(true);
     },
 
-    _fetchMediaLimits: function(invalidateCache: boolean = false) {
-        let limits;
-        if(invalidateCache || mediaLimitCache == null) {
-            MatrixClientPeg.get().getMediaLimits().then((_limits) => {
-                limits = _limits;
-            }).catch(() => {
-                // Media repo can't or won't report limits, so provide an empty object (no limits).
-                limits = {};
-            });
-            mediaLimitCache = limits;
+    _fetchMediaConfig: function(invalidateCache: boolean = false) {
+        /// NOTE: Using global here so we don't make repeated requests for the
+        /// config every time we swap room.
+        if(global.mediaConfig !== undefined && !invalidateCache) {
+            this.setState({mediaConfig: global.mediaConfig});
+            return;
         }
-        this.state.mediaLimits = limits;
+        console.log("[Media Config] Fetching");
+        MatrixClientPeg.get().getMediaConfig().then((config) => {
+            console.log("[Media Config] Fetched config:", config);
+            return config;
+        }).catch(() => {
+            // Media repo can't or won't report limits, so provide an empty object (no limits).
+            console.log("[Media Config] Could not fetch config, so not limiting uploads.");
+            return {};
+        }).then((config) => {
+            global.mediaConfig = config;
+            this.setState({mediaConfig: config});
+        });
     },
 
     _onRoomViewStoreUpdate: function(initial) {
@@ -501,8 +507,8 @@ module.exports = React.createClass({
             case 'notifier_enabled':
             case 'upload_failed':
                 // 413: File was too big or upset the server in some way.
-                if(payload.data.error.http_status === 413) {
-                    this._fetchMediaLimits(true);
+                if(payload.error.http_status === 413) {
+                    this._fetchMediaConfig(true);
                 }
             case 'upload_started':
             case 'upload_finished':
@@ -935,6 +941,15 @@ module.exports = React.createClass({
         this.setState({ draggingFile: false });
     },
 
+    isFileUploadAllowed(file) {
+        if (this.state.mediaConfig !== undefined &&
+            this.state.mediaConfig["m.upload.size"] !== undefined &&
+            file.size > this.state.mediaConfig["m.upload.size"]) {
+            return _t("File is too big. Maximum file size is %(fileSize)s", {fileSize: filesize(this.state.mediaConfig["m.upload.size"])});
+        }
+        return true;
+    },
+
     uploadFile: async function(file) {
         dis.dispatch({action: 'focus_composer'});
 
@@ -1677,7 +1692,7 @@ module.exports = React.createClass({
                     callState={this.state.callState}
                     disabled={this.props.disabled}
                     showApps={this.state.showApps}
-                    mediaLimits={this.state.mediaLimits}
+                    uploadAllowed={this.isFileUploadAllowed}
                 />;
         }
 
diff --git a/src/components/views/rooms/MessageComposer.js b/src/components/views/rooms/MessageComposer.js
index 1a80a0be4fe..f0c73a67af8 100644
--- a/src/components/views/rooms/MessageComposer.js
+++ b/src/components/views/rooms/MessageComposer.js
@@ -16,7 +16,6 @@ limitations under the License.
 */
 import React from 'react';
 import PropTypes from 'prop-types';
-import filesize from 'filesize';
 import { _t } from '../../../languageHandler';
 import CallHandler from '../../../CallHandler';
 import MatrixClientPeg from '../../../MatrixClientPeg';
@@ -102,15 +101,6 @@ export default class MessageComposer extends React.Component {
         this.uploadFiles(tfiles);
     }
 
-    isFileUploadAllowed(file) {
-        if (this.props.mediaLimits !== undefined &&
-            this.props.mediaLimits.upload_size !== undefined &&
-            file.size > this.props.mediaLimits.upload_size) {
-            return _t("File is too big. Maximum file size is %(fileSize)s", {fileSize: filesize(this.mediaLimits.upload_size)});
-        }
-        return true;
-    }
-
     uploadFiles(files) {
         const QuestionDialog = sdk.getComponent("dialogs.QuestionDialog");
         const TintableSvg = sdk.getComponent("elements.TintableSvg");
@@ -120,7 +110,7 @@ export default class MessageComposer extends React.Component {
         const failedFiles = [];
 
         for (let i=0; i<files.length; i++) {
-            const fileAcceptedOrError = this.isFileUploadAllowed(files[i]);
+            const fileAcceptedOrError = this.props.uploadAllowed(files[i]);
             if (fileAcceptedOrError === true) {
                 acceptedFiles.push(<li key={i}>
                     <TintableSvg key={i} src="img/files.svg" width="16" height="16" /> { files[i].name || _t('Attachment') }
@@ -128,7 +118,7 @@ export default class MessageComposer extends React.Component {
                 fileList.push(files[i]);
             } else {
                 failedFiles.push(<li key={i}>
-                    <TintableSvg key={i} src="img/files.svg" width="16" height="16" /> { files[i].name || _t('Attachment') } <b>{ _t('Reason') + ": " + fileAcceptedOrError}</b>
+                    <TintableSvg key={i} src="img/files.svg" width="16" height="16" /> { files[i].name || _t('Attachment') } <p>{ _t('Reason') + ": " + fileAcceptedOrError}</p>
                 </li>);
             }
         }
@@ -158,6 +148,12 @@ export default class MessageComposer extends React.Component {
                 </ul>
             </div>
         );
+        let buttonText;
+        if (acceptedFiles.length > 0 && failedFiles.length > 0) {
+            buttonText = "Upload selected"
+        } else if (failedFiles.length > 0) {
+            buttonText = "Close"
+        }
 
         Modal.createTrackedDialog('Upload Files confirmation', '', QuestionDialog, {
             title: _t('Upload Files'),
@@ -168,6 +164,8 @@ export default class MessageComposer extends React.Component {
                     { replyToWarning }
                 </div>
             ),
+            hasCancelButton: acceptedFiles.length > 0,
+            button: buttonText,
             onFinished: (shouldUpload) => {
                 if (shouldUpload) {
                     // MessageComposer shouldn't have to rely on its parent passing in a callback to upload a file
@@ -425,7 +423,8 @@ MessageComposer.propTypes = {
     // callback when a file to upload is chosen
     uploadFile: PropTypes.func.isRequired,
 
-    mediaLimits: PropTypes.object,
+    // function to test whether a file should be allowed to be uploaded.
+    uploadAllowed: PropTypes.func.isRequired,
 
     // string representing the current room app drawer state
     showApps: PropTypes.bool