diff --git a/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.test.jsx b/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.test.jsx
index 90ac1c634b..7fd923328d 100644
--- a/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.test.jsx
+++ b/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.test.jsx
@@ -311,9 +311,8 @@ describe('components/AdvancedCreateComment', () => {
         expect(wrapper.state().serverError.message).toBe(testError1);
         expect(wrapper.state().draft.uploadsInProgress).toEqual([2, 3]);
 
-        // clientId = -1
         const testError2 = 'test error 2';
-        instance.handleUploadError(testError2, -1, null, props.rootId);
+        instance.handleUploadError(testError2, '', null, props.rootId);
 
         // should not call onUpdateCommentDraft
         expect(updateCommentDraftWithRootId.mock.calls.length).toBe(1);
diff --git a/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.tsx b/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.tsx
index 6db290a676..a8b32c762d 100644
--- a/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.tsx
+++ b/webapp/channels/src/components/advanced_create_comment/advanced_create_comment.tsx
@@ -1116,8 +1116,8 @@ class AdvancedCreateComment extends React.PureComponent<Props, State> {
         }
     };
 
-    handleUploadError = (err: string | ServerError | null, clientId: string | number = -1, _?: string, rootId = '') => {
-        if (clientId !== -1) {
+    handleUploadError = (uploadError: string | ServerError | null, clientId?: string, _?: string, rootId = '') => {
+        if (clientId) {
             const draft = {...this.draftsForPost[rootId]!};
             const uploadsInProgress = [...draft.uploadsInProgress];
 
@@ -1137,16 +1137,13 @@ class AdvancedCreateComment extends React.PureComponent<Props, State> {
             }
         }
 
-        let serverError = err;
-        if (typeof serverError === 'string') {
-            serverError = new Error(serverError);
-        }
-
-        this.setState({serverError}, () => {
-            if (serverError && this.props.scrollToBottom) {
-                this.props.scrollToBottom();
+        if (typeof uploadError === 'string') {
+            if (uploadError.length !== 0) {
+                this.setState({serverError: new Error(uploadError)});
             }
-        });
+        } else {
+            this.setState({serverError: uploadError});
+        }
     };
 
     removePreview = (id: string) => {
diff --git a/webapp/channels/src/components/advanced_create_post/advanced_create_post.tsx b/webapp/channels/src/components/advanced_create_post/advanced_create_post.tsx
index 4cda2c0e8c..32d5ee2a85 100644
--- a/webapp/channels/src/components/advanced_create_post/advanced_create_post.tsx
+++ b/webapp/channels/src/components/advanced_create_post/advanced_create_post.tsx
@@ -1038,34 +1038,32 @@ class AdvancedCreatePost extends React.PureComponent<Props, State> {
         this.handleDraftChange(draft, true);
     };
 
-    handleUploadError = (err: string | ServerError, clientId?: string, channelId?: string) => {
-        let serverError = err;
-        if (typeof serverError === 'string') {
-            serverError = new Error(serverError);
-        }
+    handleUploadError = (uploadError: string | ServerError | null, clientId?: string, channelId?: string) => {
+        if (clientId && channelId) {
+            const draft = {...this.draftsForChannel[channelId]!};
 
-        if (!channelId || !clientId) {
-            this.setState({serverError});
-            return;
-        }
+            if (draft.uploadsInProgress) {
+                const index = draft.uploadsInProgress.indexOf(clientId);
 
-        const draft = {...this.draftsForChannel[channelId]!};
-
-        if (draft.uploadsInProgress) {
-            const index = draft.uploadsInProgress.indexOf(clientId);
-
-            if (index !== -1) {
-                const uploadsInProgress = draft.uploadsInProgress.filter((item, itemIndex) => index !== itemIndex);
-                const modifiedDraft = {
-                    ...draft,
-                    uploadsInProgress,
-                };
-                this.props.actions.setDraft(StoragePrefixes.DRAFT + channelId, modifiedDraft, channelId);
-                this.draftsForChannel[channelId] = modifiedDraft;
+                if (index !== -1) {
+                    const uploadsInProgress = draft.uploadsInProgress.filter((item, itemIndex) => index !== itemIndex);
+                    const modifiedDraft = {
+                        ...draft,
+                        uploadsInProgress,
+                    };
+                    this.props.actions.setDraft(StoragePrefixes.DRAFT + channelId, modifiedDraft, channelId);
+                    this.draftsForChannel[channelId] = modifiedDraft;
+                }
             }
         }
 
-        this.setState({serverError});
+        if (typeof uploadError === 'string') {
+            if (uploadError.length !== 0) {
+                this.setState({serverError: new Error(uploadError)});
+            }
+        } else {
+            this.setState({serverError: uploadError});
+        }
     };
 
     removePreview = (id: string) => {
diff --git a/webapp/channels/src/components/advanced_text_editor/advanced_text_editor.tsx b/webapp/channels/src/components/advanced_text_editor/advanced_text_editor.tsx
index dfdc290b5d..41c8a67b3b 100644
--- a/webapp/channels/src/components/advanced_text_editor/advanced_text_editor.tsx
+++ b/webapp/channels/src/components/advanced_text_editor/advanced_text_editor.tsx
@@ -88,7 +88,7 @@ type Props = {
     hideEmojiPicker: () => void;
     toggleAdvanceTextEditor: () => void;
     handleUploadProgress: (filePreviewInfo: FilePreviewInfo) => void;
-    handleUploadError: (err: string | ServerError, clientId?: string, channelId?: string) => void;
+    handleUploadError: (err: string | ServerError | null, clientId?: string, channelId?: string) => void;
     handleFileUploadComplete: (fileInfos: FileInfo[], clientIds: string[], channelId: string, rootId?: string) => void;
     handleUploadStart: (clientIds: string[], channelId: string) => void;
     handleFileUploadChange: () => void;
@@ -199,17 +199,6 @@ const AdvanceTextEditor = ({
         setKeepEditorInFocus(true);
     }, []);
 
-    let serverErrorJsx = null;
-    if (serverError) {
-        serverErrorJsx = (
-            <MessageSubmitError
-                error={serverError}
-                submittedMessage={serverError.submittedMessage}
-                handleSubmit={handleSubmit}
-            />
-        );
-    }
-
     let attachmentPreview = null;
     if (!readOnlyChannel && (draft.fileInfos.length > 0 || draft.uploadsInProgress.length > 0)) {
         attachmentPreview = (
@@ -551,12 +540,20 @@ const AdvanceTextEditor = ({
             <div
                 id='postCreateFooter'
                 role='form'
-                className={classNames('AdvancedTextEditor__footer', {
-                    'AdvancedTextEditor__footer--has-error': postError || serverError,
-                })}
+                className={classNames('AdvancedTextEditor__footer', {'AdvancedTextEditor__footer--has-error': postError || serverError})}
             >
-                {postError && <label className={classNames('post-error', {errorClass})}>{postError}</label>}
-                {serverErrorJsx}
+                {postError && (
+                    <label className={classNames('post-error', {errorClass})}>
+                        {postError}
+                    </label>
+                )}
+                {serverError && (
+                    <MessageSubmitError
+                        error={serverError}
+                        submittedMessage={serverError.submittedMessage}
+                        handleSubmit={handleSubmit}
+                    />
+                )}
                 <MsgTyping
                     channelId={channelId}
                     postId={postId}
diff --git a/webapp/channels/src/components/file_upload/file_upload.test.tsx b/webapp/channels/src/components/file_upload/file_upload.test.tsx
index 9333fe7001..e7b75a6b91 100644
--- a/webapp/channels/src/components/file_upload/file_upload.test.tsx
+++ b/webapp/channels/src/components/file_upload/file_upload.test.tsx
@@ -3,17 +3,15 @@
 
 import React, {MouseEvent, DragEvent, ChangeEvent} from 'react';
 
+import {FileInfo} from '@mattermost/types/files';
+
 import {General} from 'mattermost-redux/constants';
 
-import {clearFileInput} from 'utils/utils';
-
-import {shallowWithIntl} from 'tests/helpers/intl-test-helper';
-
 import FileUpload, {FileUpload as FileUploadClass} from 'components/file_upload/file_upload';
 
+import {clearFileInput} from 'utils/utils';
 import {FilesWillUploadHook} from 'types/store/plugins';
-
-import {FileInfo} from '@mattermost/types/files';
+import {shallowWithIntl} from 'tests/helpers/intl-test-helper';
 
 const generatedIdRegex = /[a-z0-9]{8}-[a-z0-9]{4}-[a-z0-9]{4}-[a-z0-9]{4}-[a-z0-9]{12}/;
 
@@ -266,7 +264,7 @@ describe('components/FileUpload', () => {
         );
 
         expect(baseProps.onUploadError).toHaveBeenCalledTimes(1);
-        expect(baseProps.onUploadError).toHaveBeenCalledWith('');
+        expect(baseProps.onUploadError).toHaveBeenCalledWith(null);
     });
 
     test('should error max upload files', () => {
@@ -286,7 +284,7 @@ describe('components/FileUpload', () => {
         expect(baseProps.onUploadStart).toBeCalledWith([], props.channelId);
 
         expect(baseProps.onUploadError).toHaveBeenCalledTimes(2);
-        expect(baseProps.onUploadError.mock.calls[0][0]).toEqual('');
+        expect(baseProps.onUploadError.mock.calls[0][0]).toEqual(null);
     });
 
     test('should error max upload files', () => {
@@ -306,7 +304,7 @@ describe('components/FileUpload', () => {
         expect(baseProps.onUploadStart).toBeCalledWith([], props.channelId);
 
         expect(baseProps.onUploadError).toHaveBeenCalledTimes(2);
-        expect(baseProps.onUploadError.mock.calls[0][0]).toEqual('');
+        expect(baseProps.onUploadError.mock.calls[0][0]).toEqual(null);
     });
 
     test('should error max too large files', () => {
@@ -324,7 +322,7 @@ describe('components/FileUpload', () => {
         expect(baseProps.onUploadStart).toBeCalledWith([], baseProps.channelId);
 
         expect(baseProps.onUploadError).toHaveBeenCalledTimes(2);
-        expect(baseProps.onUploadError.mock.calls[0][0]).toEqual('');
+        expect(baseProps.onUploadError.mock.calls[0][0]).toEqual(null);
     });
 
     test('should functions when handleChange is called', () => {
@@ -358,7 +356,7 @@ describe('components/FileUpload', () => {
         instance.handleDrop(e);
 
         expect(baseProps.onUploadError).toBeCalled();
-        expect(baseProps.onUploadError).toHaveBeenCalledWith('');
+        expect(baseProps.onUploadError).toHaveBeenCalledWith(null);
 
         expect(instance.uploadFiles).toBeCalled();
         expect(instance.uploadFiles).toHaveBeenCalledWith(e.dataTransfer.files);
@@ -386,7 +384,7 @@ describe('components/FileUpload', () => {
         expect(baseProps.onUploadStart).toHaveBeenCalledTimes(0);
 
         expect(baseProps.onUploadError).toHaveBeenCalledTimes(1);
-        expect(baseProps.onUploadError).toHaveBeenCalledWith('');
+        expect(baseProps.onUploadError).toHaveBeenCalledWith(null);
     });
 
     test('FilesWillUploadHook - should reject one file and allow one file', () => {
@@ -409,6 +407,6 @@ describe('components/FileUpload', () => {
         expect(baseProps.onUploadStart).toHaveBeenCalledWith([expect.stringMatching(generatedIdRegex)], props.channelId);
 
         expect(baseProps.onUploadError).toHaveBeenCalledTimes(1);
-        expect(baseProps.onUploadError).toHaveBeenCalledWith('');
+        expect(baseProps.onUploadError).toHaveBeenCalledWith(null);
     });
 });
diff --git a/webapp/channels/src/components/file_upload/file_upload.tsx b/webapp/channels/src/components/file_upload/file_upload.tsx
index db03376790..a41f617af5 100644
--- a/webapp/channels/src/components/file_upload/file_upload.tsx
+++ b/webapp/channels/src/components/file_upload/file_upload.tsx
@@ -120,7 +120,7 @@ export type Props = {
     /**
      * Function to be called when upload fails
      */
-    onUploadError: (err: string | ServerError, clientId?: string, channelId?: string, currentRootId?: string) => void;
+    onUploadError: (err: string | ServerError | null, clientId?: string, channelId?: string, currentRootId?: string) => void;
 
     /**
      * Function to be called when file upload starts
@@ -222,13 +222,13 @@ export class FileUpload extends PureComponent<Props, State> {
 
     pluginUploadFiles = (files: File[]) => {
         // clear any existing errors
-        this.props.onUploadError('');
+        this.props.onUploadError(null);
         this.uploadFiles(files);
     };
 
     checkPluginHooksAndUploadFiles = (files: FileList | File[]) => {
         // clear any existing errors
-        this.props.onUploadError('');
+        this.props.onUploadError(null);
 
         let sortedFiles = Array.from(files).sort((a, b) => a.name.localeCompare(b.name, this.props.locale, {numeric: true}));
 
@@ -335,7 +335,7 @@ export class FileUpload extends PureComponent<Props, State> {
             return;
         }
 
-        this.props.onUploadError('');
+        this.props.onUploadError(null);
 
         const items = e.dataTransfer.items || [];
         const droppedFiles = e.dataTransfer.files;
@@ -460,7 +460,7 @@ export class FileUpload extends PureComponent<Props, State> {
             return;
         }
 
-        this.props.onUploadError('');
+        this.props.onUploadError(null);
 
         const items = [];
         for (let i = 0; i < e.clipboardData.items.length; i++) {
diff --git a/webapp/channels/src/components/message_submit_error.tsx b/webapp/channels/src/components/message_submit_error.tsx
index 1de774514c..bb8c5075dd 100644
--- a/webapp/channels/src/components/message_submit_error.tsx
+++ b/webapp/channels/src/components/message_submit_error.tsx
@@ -1,68 +1,56 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See LICENSE.txt for license information.
 
-import React, {ReactFragment} from 'react';
+import React, {MouseEventHandler} from 'react';
 import {FormattedMessage} from 'react-intl';
 
 import {ServerError} from '@mattermost/types/errors';
 
 import {isErrorInvalidSlashCommand} from 'utils/post_utils';
 
-interface MessageSubmitErrorProps {
+interface Props {
     error: ServerError;
-    handleSubmit: (e: React.MouseEvent<HTMLAnchorElement, MouseEvent>) => void;
+    handleSubmit: MouseEventHandler<HTMLAnchorElement>;
     submittedMessage?: string;
 }
 
-class MessageSubmitError extends React.PureComponent<MessageSubmitErrorProps> {
-    public renderSlashCommandError = (): string | ReactFragment => {
-        if (!this.props.submittedMessage) {
-            return this.props.error.message;
-        }
-
-        const command = this.props.submittedMessage.split(' ')[0];
-        return (
-            <React.Fragment>
-                <FormattedMessage
-                    id='message_submit_error.invalidCommand'
-                    defaultMessage="Command with a trigger of ''{command}'' not found. "
-                    values={{
-                        command,
-                    }}
-                />
-                <a
-                    href='#'
-                    onClick={this.props.handleSubmit}
-                >
-                    <FormattedMessage
-                        id='message_submit_error.sendAsMessageLink'
-                        defaultMessage='Click here to send as a message.'
-                    />
-                </a>
-            </React.Fragment>
-        );
-    };
-
-    public render(): JSX.Element | null {
-        const error = this.props.error;
-
-        if (!error) {
-            return null;
-        }
-
-        let errorContent: string | ReactFragment = error.message;
-        if (isErrorInvalidSlashCommand(error)) {
-            errorContent = this.renderSlashCommandError();
-        }
+function MessageSubmitError(props: Props) {
+    if (isErrorInvalidSlashCommand(props.error)) {
+        const slashCommand = props.submittedMessage?.split(' ')[0];
 
         return (
             <div className='has-error'>
                 <label className='control-label'>
-                    {errorContent}
+                    <FormattedMessage
+                        id='message_submit_error.invalidCommand'
+                        defaultMessage="Command with a trigger of ''{slashCommand}'' not found. "
+                        values={{
+                            slashCommand,
+                        }}
+                    />
+                    <a
+                        href='#'
+                        onClick={props.handleSubmit}
+                    >
+                        <FormattedMessage
+                            id='message_submit_error.sendAsMessageLink'
+                            defaultMessage='Click here to send as a message.'
+                        />
+                    </a>
                 </label>
             </div>
         );
     }
+
+    if (props.error?.message?.trim()?.length === 0) {
+        return null;
+    }
+
+    return (
+        <div className='has-error'>
+            <label className='control-label'>{props.error.message.trim()}</label>
+        </div>
+    );
 }
 
 export default MessageSubmitError;