diff --git a/assets/src/components/files/Listing.vue b/assets/src/components/files/Listing.vue
index af7a8c6b..cb4e818d 100644
--- a/assets/src/components/files/Listing.vue
+++ b/assets/src/components/files/Listing.vue
@@ -8,7 +8,6 @@
   </div>
   <div v-else id="listing"
     :class="req.display"
-    @drop="drop"
     @dragenter="dragEnter"
     @dragend="dragEnd">
     <div>
@@ -230,7 +229,7 @@ export default {
       if (columns === 0) columns = 1
       items.style.width = `calc(${100 / columns}% - 1em)`
     },
-    dragEnter: function (event) {
+    dragEnter (event) {
       // When the user starts dragging an item, put every
       // file on the listing with 50% opacity.
       let items = document.getElementsByClassName('item')
@@ -239,51 +238,85 @@ export default {
         file.style.opacity = 0.5
       })
     },
-    dragEnd: function (event) {
+    dragEnd (event) {
       this.resetOpacity()
     },
     drop: function (event) {
       event.preventDefault()
+      this.resetOpacity()
 
       let dt = event.dataTransfer
       let files = dt.files
       let el = event.target
 
+      if (files.length <= 0) return
+
       for (let i = 0; i < 5; i++) {
         if (el !== null && !el.classList.contains('item')) {
           el = el.parentElement
         }
       }
 
-      if (files.length > 0) {
-        if (el !== null && el.classList.contains('item') && el.dataset.dir === 'true') {
-          this.handleFiles(files, el.querySelector('.name').innerHTML + '/')
-          return
-        }
-
-        this.handleFiles(files, '')
-      } else {
-        this.resetOpacity()
+      let base = ''
+      if (el !== null && el.classList.contains('item') && el.dataset.dir === 'true') {
+        base = el.querySelector('.name').innerHTML + '/'
       }
+
+      if (base !== '') {
+        api.fetch(this.$route.path + base)
+          .then(req => {
+            this.checkConflict(files, req.items, base)
+          })
+          .catch(error => { console.log(error) })
+
+        return
+      }
+
+      this.checkConflict(files, this.req.items, base)
     },
-    uploadInput: function (event) {
-      this.handleFiles(event.currentTarget.files, '')
+    checkConflict (files, items, base) {
+      let conflict = false
+      for (let i = 0; i < files.length; i++) {
+        let res = items.findIndex(function hasConflict (element) {
+          return (element.name === this)
+        }, files[i].name)
+
+        if (res >= 0) {
+          conflict = true
+          break
+        }
+      }
+
+      if (!conflict) {
+        this.handleFiles(files, base)
+        return
+      }
+
+      this.$store.commit('showHover', {
+        prompt: 'replace',
+        confirm: (event) => {
+          event.preventDefault()
+          this.$store.commit('closeHovers')
+          this.handleFiles(files, base, true)
+        }
+      })
     },
-    resetOpacity: function () {
+    uploadInput (event) {
+      this.checkConflict(event.currentTarget.files, this.req.items, '')
+    },
+    resetOpacity () {
       let items = document.getElementsByClassName('item')
 
       Array.from(items).forEach(file => {
         file.style.opacity = 1
       })
     },
-    handleFiles: function (files, base) {
-      this.resetOpacity()
-
+    handleFiles (files, base, overwrite = false) {
       buttons.loading('upload')
       let promises = []
 
       for (let file of files) {
-        promises.push(api.post(this.$route.path + base + file.name, file))
+        promises.push(api.post(this.$route.path + base + file.name, file, overwrite))
       }
 
       Promise.all(promises)
diff --git a/assets/src/components/files/ListingItem.vue b/assets/src/components/files/ListingItem.vue
index 81c7be12..eb67d095 100644
--- a/assets/src/components/files/ListingItem.vue
+++ b/assets/src/components/files/ListingItem.vue
@@ -9,6 +9,7 @@
   @click="click"
   @dblclick="open"
   @touchstart="touchstart"
+  :data-dir="isDir"
   :aria-label="name"
   :aria-selected="isSelected">
     <div>
diff --git a/assets/src/components/prompts/Prompts.vue b/assets/src/components/prompts/Prompts.vue
index f42d7369..781bbe16 100644
--- a/assets/src/components/prompts/Prompts.vue
+++ b/assets/src/components/prompts/Prompts.vue
@@ -11,6 +11,7 @@
     <copy v-else-if="showCopy"></copy>
     <error v-else-if="showError"></error>
     <success v-else-if="showSuccess"></success>
+    <replace v-else-if="showReplace"></replace>
 
     <template v-for="plugin in plugins">
       <form class="prompt"
@@ -54,6 +55,7 @@ import Error from './Error'
 import Success from './Success'
 import NewFile from './NewFile'
 import NewDir from './NewDir'
+import Replace from './Replace'
 import { mapState } from 'vuex'
 import buttons from '@/utils/buttons'
 import api from '@/utils/api'
@@ -71,7 +73,8 @@ export default {
     Copy,
     NewFile,
     NewDir,
-    Help
+    Help,
+    Replace
   },
   data: function () {
     return {
@@ -96,6 +99,7 @@ export default {
     showNewFile: function () { return this.show === 'newFile' },
     showNewDir: function () { return this.show === 'newDir' },
     showDownload: function () { return this.show === 'download' },
+    showReplace: function () { return this.show === 'replace' },
     showOverlay: function () {
       return (this.show !== null && this.show !== 'search' && this.show !== 'more')
     }
diff --git a/assets/src/components/prompts/Replace.vue b/assets/src/components/prompts/Replace.vue
new file mode 100644
index 00000000..a7da4331
--- /dev/null
+++ b/assets/src/components/prompts/Replace.vue
@@ -0,0 +1,26 @@
+<template>
+  <div class="prompt">
+    <h3>{{ $t('prompts.replace') }}</h3>
+    <p>{{ $t('prompts.replaceMessage') }}</p>
+
+    <div>
+      <button class="ok"
+        @click="showConfirm"
+        :aria-label="$t('buttons.replace')"
+        :title="$t('buttons.replace')">{{ $t('buttons.replace') }}</button>
+      <button class="cancel"
+        @click="$store.commit('closeHovers')"
+        :aria-label="$t('buttons.cancel')"
+        :title="$t('buttons.cancel')">{{ $t('buttons.cancel') }}</button>
+    </div>
+  </div>
+</template>
+
+<script>
+import { mapState } from 'vuex'
+
+export default {
+  name: 'replace',
+  computed: mapState(['showConfirm'])
+}
+</script>
diff --git a/assets/src/i18n/en.yaml b/assets/src/i18n/en.yaml
index 2157ad95..2326a176 100644
--- a/assets/src/i18n/en.yaml
+++ b/assets/src/i18n/en.yaml
@@ -13,6 +13,7 @@ buttons:
   new: New
   next: Next
   ok: OK
+  replace: Replace
   previous: Previous
   rename: Rename
   reportIssue: Report Issue
@@ -84,6 +85,10 @@ prompts:
   newFileMessage: Write the name of the new file.
   numberDirs: Number of directories
   numberFiles: Number of files
+  replace: Replace
+  replaceMessage: >
+    One of the files you're trying to upload is conflicting because of its name.
+    Do you wish to replace the existing one?
   rename: Rename
   renameMessage: Insert a new name for
   show: Show
diff --git a/assets/src/i18n/pt.yaml b/assets/src/i18n/pt.yaml
index 8edf4160..eb758cdd 100644
--- a/assets/src/i18n/pt.yaml
+++ b/assets/src/i18n/pt.yaml
@@ -15,6 +15,7 @@ buttons:
   ok: OK
   previous: Anterior
   rename: Renomear
+  replace: Substituir
   reportIssue: Reportar Erro
   save: Guardar
   search: Pesquisar
@@ -86,6 +87,10 @@ prompts:
   numberFiles: Número de ficheiros
   rename: Renomear
   renameMessage: Insira um novo nome para
+  replace: Substituir
+  replaceMessage: >
+    Já existe um ficheiro com nome igual a um dos que está a tentar enviar. Deseja
+    substituir?
   show: Mostrar
   size: Tamanho
 settings:
diff --git a/assets/src/store/index.js b/assets/src/store/index.js
index 6d851b91..9c68cb6a 100644
--- a/assets/src/store/index.js
+++ b/assets/src/store/index.js
@@ -20,7 +20,8 @@ const state = {
   selected: [],
   multiple: false,
   show: null,
-  showMessage: null
+  showMessage: null,
+  showConfirm: null
 }
 
 export default new Vuex.Store({
diff --git a/assets/src/store/mutations.js b/assets/src/store/mutations.js
index 481845f2..d88ac91b 100644
--- a/assets/src/store/mutations.js
+++ b/assets/src/store/mutations.js
@@ -13,6 +13,7 @@ const mutations = {
 
     state.show = value.prompt
     state.showMessage = value.message
+    state.showConfirm = value.confirm
   },
   showError: (state, value) => {
     state.show = 'error'
diff --git a/assets/src/utils/api.js b/assets/src/utils/api.js
index 04fff2cd..3ada5927 100644
--- a/assets/src/utils/api.js
+++ b/assets/src/utils/api.js
@@ -4,9 +4,11 @@ const ssl = (window.location.protocol === 'https:')
 
 export function removePrefix (url) {
   if (url.startsWith('/files')) {
-    return url.slice(6)
+    url = url.slice(6)
   }
 
+  if (url === '') url = '/'
+  if (url[0] !== '/') url = '/' + url
   return url
 }
 
@@ -54,7 +56,7 @@ export function rm (url) {
   })
 }
 
-export function post (url, content = '') {
+export function post (url, content = '', overwrite = false) {
   url = removePrefix(url)
 
   return new Promise((resolve, reject) => {
@@ -62,15 +64,23 @@ export function post (url, content = '') {
     request.open('POST', `${store.state.baseURL}/api/resource${url}`, true)
     request.setRequestHeader('Authorization', `Bearer ${store.state.jwt}`)
 
+    if (overwrite) {
+      request.setRequestHeader('Action', `override`)
+    }
+
     request.onload = () => {
       if (request.status === 200) {
         resolve(request.responseText)
+      } else if (request.status === 409) {
+        reject(request.status)
       } else {
         reject(request.responseText)
       }
     }
 
-    request.onerror = (error) => reject(error)
+    request.onerror = (error) => {
+      reject(error)
+    }
     request.send(content)
   })
 }
diff --git a/resource.go b/resource.go
index 6eff1db6..792c5687 100644
--- a/resource.go
+++ b/resource.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net/http"
 	"net/url"
 	"os"
@@ -155,6 +156,12 @@ func resourcePostPutHandler(c *RequestContext, w http.ResponseWriter, r *http.Re
 		return http.StatusForbidden, nil
 	}
 
+	// Discard any invalid upload before returning to avoid connection
+	// reset error.
+	defer func() {
+		io.Copy(ioutil.Discard, r.Body)
+	}()
+
 	// Checks if the current request is for a directory and not a file.
 	if strings.HasSuffix(r.URL.Path, "/") {
 		// If the method is PUT, we return 405 Method not Allowed, because
@@ -171,7 +178,7 @@ func resourcePostPutHandler(c *RequestContext, w http.ResponseWriter, r *http.Re
 	// If using POST method, we are trying to create a new file so it is not
 	// desirable to override an already existent file. Thus, we check
 	// if the file already exists. If so, we just return a 409 Conflict.
-	if r.Method == http.MethodPost {
+	if r.Method == http.MethodPost && r.Header.Get("Action") != "override" {
 		if _, err := c.User.FileSystem.Stat(r.URL.Path); err == nil {
 			return http.StatusConflict, errors.New("There is already a file on that path")
 		}