diff --git a/blocking.py b/blocking.py
index fed8af9a5..836f85ca2 100644
--- a/blocking.py
+++ b/blocking.py
@@ -67,7 +67,7 @@ def removeGlobalBlock(baseDir: str,
         if os.path.isfile(unblockingFilename):
             if unblockHandle in open(unblockingFilename).read():
                 with open(unblockingFilename, 'r') as fp:
-                    with open(unblockingFilename + '.new', 'w') as fpnew:
+                    with open(unblockingFilename + '.new', 'w+') as fpnew:
                         for line in fp:
                             handle = line.replace('\n', '').replace('\r', '')
                             if unblockHandle not in line:
@@ -80,7 +80,7 @@ def removeGlobalBlock(baseDir: str,
         if os.path.isfile(unblockingFilename):
             if unblockHashtag + '\n' in open(unblockingFilename).read():
                 with open(unblockingFilename, 'r') as fp:
-                    with open(unblockingFilename + '.new', 'w') as fpnew:
+                    with open(unblockingFilename + '.new', 'w+') as fpnew:
                         for line in fp:
                             blockLine = \
                                 line.replace('\n', '').replace('\r', '')
@@ -104,7 +104,7 @@ def removeBlock(baseDir: str, nickname: str, domain: str,
     if os.path.isfile(unblockingFilename):
         if unblockHandle in open(unblockingFilename).read():
             with open(unblockingFilename, 'r') as fp:
-                with open(unblockingFilename + '.new', 'w') as fpnew:
+                with open(unblockingFilename + '.new', 'w+') as fpnew:
                     for line in fp:
                         handle = line.replace('\n', '').replace('\r', '')
                         if unblockHandle not in line:
diff --git a/bookmarks.py b/bookmarks.py
index 0039a6d89..22387d395 100644
--- a/bookmarks.py
+++ b/bookmarks.py
@@ -57,7 +57,7 @@ def undoBookmarksCollectionEntry(recentPostsCache: {},
     indexStr = ''
     with open(bookmarksIndexFilename, 'r') as indexFile:
         indexStr = indexFile.read().replace(bookmarkIndex + '\n', '')
-        bookmarksIndexFile = open(bookmarksIndexFilename, 'w')
+        bookmarksIndexFile = open(bookmarksIndexFilename, 'w+')
         if bookmarksIndexFile:
             bookmarksIndexFile.write(indexStr)
             bookmarksIndexFile.close()
@@ -213,7 +213,7 @@ def updateBookmarksCollection(recentPostsCache: {},
                     print('WARN: Failed to write entry to bookmarks index ' +
                           bookmarksIndexFilename + ' ' + str(e))
         else:
-            bookmarksIndexFile = open(bookmarksIndexFilename, 'w')
+            bookmarksIndexFile = open(bookmarksIndexFilename, 'w+')
             if bookmarksIndexFile:
                 bookmarksIndexFile.write(bookmarkIndex + '\n')
                 bookmarksIndexFile.close()
diff --git a/daemon.py b/daemon.py
index 679aadeb3..6795a1504 100644
--- a/daemon.py
+++ b/daemon.py
@@ -292,7 +292,7 @@ class PubServer(BaseHTTPRequestHandler):
         if not minimal and minimalFileExists:
             os.remove(minimalFilename)
         elif minimal and not minimalFileExists:
-            with open(minimalFilename, 'w') as fp:
+            with open(minimalFilename, 'w+') as fp:
                 fp.write('\n')
 
     def _sendReplyToQuestion(self, nickname: str, messageId: str,
@@ -539,7 +539,7 @@ class PubServer(BaseHTTPRequestHandler):
         if not etag:
             etag = sha1(data).hexdigest()  # nosec
             try:
-                with open(mediaFilename + '.etag', 'w') as etagFile:
+                with open(mediaFilename + '.etag', 'w+') as etagFile:
                     etagFile.write(etag)
             except BaseException:
                 pass
@@ -5108,7 +5108,7 @@ class PubServer(BaseHTTPRequestHandler):
                             mediaBinary = avFile.read()
                             etag = sha1(mediaBinary).hexdigest()  # nosec
                             try:
-                                with open(mediaTagFilename, 'w') as etagFile:
+                                with open(mediaTagFilename, 'w+') as etagFile:
                                     etagFile.write(etag)
                             except BaseException:
                                 pass
@@ -5255,7 +5255,7 @@ class PubServer(BaseHTTPRequestHandler):
                 self.server.baseDir + '/accounts/' + \
                 nickname + '@' + self.server.domain + '/.lastUsed'
             try:
-                lastUsedFile = open(lastUsedFilename, 'w')
+                lastUsedFile = open(lastUsedFilename, 'w+')
                 if lastUsedFile:
                     lastUsedFile.write(str(int(time.time())))
                     lastUsedFile.close()
@@ -5903,7 +5903,7 @@ class PubServer(BaseHTTPRequestHandler):
                                   loginNickname + ' ' + str(e))
                     else:
                         try:
-                            with open(saltFilename, 'w') as fp:
+                            with open(saltFilename, 'w+') as fp:
                                 fp.write(salt)
                         except Exception as e:
                             print('WARN: Unable to save salt for ' +
@@ -5917,7 +5917,7 @@ class PubServer(BaseHTTPRequestHandler):
                         self.server.baseDir+'/accounts/' + \
                         loginHandle + '/.token'
                     try:
-                        with open(tokenFilename, 'w') as fp:
+                        with open(tokenFilename, 'w+') as fp:
                             fp.write(token)
                     except Exception as e:
                         print('WARN: Unable to save token for ' +
diff --git a/epicyon.py b/epicyon.py
index c8271e636..a6a8bd900 100644
--- a/epicyon.py
+++ b/epicyon.py
@@ -479,7 +479,7 @@ if args.socnet:
                               httpPrefix, debug,
                               __version__)
     try:
-        with open('socnet.dot', 'w') as fp:
+        with open('socnet.dot', 'w+') as fp:
             fp.write(dotGraph)
             print('Saved to socnet.dot')
     except BaseException:
diff --git a/filters.py b/filters.py
index 81335234b..744e28775 100644
--- a/filters.py
+++ b/filters.py
@@ -32,7 +32,7 @@ def removeFilter(baseDir: str, nickname: str, domain: str,
     if os.path.isfile(filtersFilename):
         if words in open(filtersFilename).read():
             with open(filtersFilename, 'r') as fp:
-                with open(filtersFilename + '.new', 'w') as fpnew:
+                with open(filtersFilename + '.new', 'w+') as fpnew:
                     for line in fp:
                         line = line.replace('\n', '')
                         if line != words:
diff --git a/followingCalendar.py b/followingCalendar.py
index f414634b7..10c5ae39e 100644
--- a/followingCalendar.py
+++ b/followingCalendar.py
@@ -29,7 +29,7 @@ def receivingCalendarEvents(baseDir: str, nickname: str, domain: str,
         # create a new calendar file from the following file
         with open(followingFilename, 'r') as followingFile:
             followingHandles = followingFile.read()
-            with open(calendarFilename, 'w') as fp:
+            with open(calendarFilename, 'w+') as fp:
                 fp.write(followingHandles)
     return handle + '\n' in open(calendarFilename).read()
 
@@ -65,7 +65,7 @@ def receiveCalendarEvents(baseDir: str, nickname: str, domain: str,
         # create a new calendar file from the following file
         with open(followingFilename, 'r') as followingFile:
             followingHandles = followingFile.read()
-            with open(calendarFilename, 'w') as fp:
+            with open(calendarFilename, 'w+') as fp:
                 fp.write(followingHandles)
 
     # already in the calendar file?
@@ -75,14 +75,14 @@ def receiveCalendarEvents(baseDir: str, nickname: str, domain: str,
             return
         # remove from calendar file
         followingHandles = followingHandles.replace(handle + '\n', '')
-        with open(calendarFilename, 'w') as fp:
+        with open(calendarFilename, 'w+') as fp:
             fp.write(followingHandles)
     else:
         # not already in the calendar file
         if add:
             # append to the list of handles
             followingHandles += handle + '\n'
-            with open(calendarFilename, 'w') as fp:
+            with open(calendarFilename, 'w+') as fp:
                 fp.write(followingHandles)
 
 
diff --git a/inbox.py b/inbox.py
index c8545e49a..ffeaed505 100644
--- a/inbox.py
+++ b/inbox.py
@@ -1702,7 +1702,7 @@ def dmNotify(baseDir: str, handle: str, url: str) -> None:
         return
     dmFile = accountDir + '/.newDM'
     if not os.path.isfile(dmFile):
-        with open(dmFile, 'w') as fp:
+        with open(dmFile, 'w+') as fp:
             fp.write(url)
 
 
@@ -1748,10 +1748,16 @@ def likeNotify(baseDir: str, domain: str, onionDomain: str,
                 prevLikeStr = likeFile.read()
                 if prevLikeStr == likeStr:
                     return
-        with open(prevLikeFile, 'w') as fp:
-            fp.write(likeStr)
-        with open(likeFile, 'w') as fp:
-            fp.write(likeStr)
+        try:
+            with open(prevLikeFile, 'w+') as fp:
+                fp.write(likeStr)
+        except BaseException:
+            pass
+        try:
+            with open(likeFile, 'w+') as fp:
+                fp.write(likeStr)
+        except BaseException:
+            pass
 
 
 def replyNotify(baseDir: str, handle: str, url: str) -> None:
@@ -1762,7 +1768,7 @@ def replyNotify(baseDir: str, handle: str, url: str) -> None:
         return
     replyFile = accountDir + '/.newReply'
     if not os.path.isfile(replyFile):
-        with open(replyFile, 'w') as fp:
+        with open(replyFile, 'w+') as fp:
             fp.write(url)
 
 
@@ -1777,7 +1783,7 @@ def gitPatchNotify(baseDir: str, handle: str,
     patchFile = accountDir + '/.newPatch'
     subject = subject.replace('[PATCH]', '').strip()
     handle = '@' + fromNickname + '@' + fromDomain
-    with open(patchFile, 'w') as fp:
+    with open(patchFile, 'w+') as fp:
         fp.write('git ' + handle + ' ' + subject)
 
 
@@ -1949,7 +1955,7 @@ def inboxUpdateCalendar(baseDir: str, handle: str, postJsonObject: {}) -> None:
             calendarNotificationFilename = \
                 baseDir + '/accounts/' + handle + '/.newCalendar'
             calendarNotificationFile = \
-                open(calendarNotificationFilename, 'w')
+                open(calendarNotificationFilename, 'w+')
             if calendarNotificationFile:
                 calendarNotificationFile.write('/calendar?year=' +
                                                str(eventYear) +
diff --git a/media.py b/media.py
index 4afa96571..7c6b87306 100644
--- a/media.py
+++ b/media.py
@@ -122,7 +122,7 @@ def updateEtag(mediaFilename: str) -> None:
     etag = sha1(data).hexdigest()  # nosec
     # save the hash
     try:
-        with open(mediaFilename + '.etag', 'w') as etagFile:
+        with open(mediaFilename + '.etag', 'w+') as etagFile:
             etagFile.write(etag)
     except BaseException:
         pass
diff --git a/migrate.py b/migrate.py
index ac9502e03..6fb8bee28 100644
--- a/migrate.py
+++ b/migrate.py
@@ -25,7 +25,7 @@ def migrateFollows(followFilename: str, oldHandle: str,
     newFollowData = followData.replace(oldHandle, newHandle)
     if followData == newFollowData:
         return
-    with open(followFilename, 'w') as followFile:
+    with open(followFilename, 'w+') as followFile:
         followFile.write(newFollowData)
 
 
diff --git a/person.py b/person.py
index 0e6252b49..78b20a01e 100644
--- a/person.py
+++ b/person.py
@@ -1004,7 +1004,7 @@ def isPersonSnoozed(baseDir: str, nickname: str, domain: str,
         with open(snoozedFilename, 'r') as snoozedFile:
             content = snoozedFile.read().replace(replaceStr, '')
         if content:
-            writeSnoozedFile = open(snoozedFilename, 'w')
+            writeSnoozedFile = open(snoozedFilename, 'w+')
             if writeSnoozedFile:
                 writeSnoozedFile.write(content)
                 writeSnoozedFile.close()
@@ -1057,7 +1057,7 @@ def personUnsnooze(baseDir: str, nickname: str, domain: str,
         with open(snoozedFilename, 'r') as snoozedFile:
             content = snoozedFile.read().replace(replaceStr, '')
         if content:
-            writeSnoozedFile = open(snoozedFilename, 'w')
+            writeSnoozedFile = open(snoozedFilename, 'w+')
             if writeSnoozedFile:
                 writeSnoozedFile.write(content)
                 writeSnoozedFile.close()
diff --git a/petnames.py b/petnames.py
index e28048250..7046a5d94 100644
--- a/petnames.py
+++ b/petnames.py
@@ -40,7 +40,7 @@ def setPetName(baseDir: str, nickname: str, domain: str,
                     else:
                         newPetnamesStr += entry
                 # save the updated petnames file
-                with open(petnamesFilename, 'w') as petnamesFile:
+                with open(petnamesFilename, 'w+') as petnamesFile:
                     petnamesFile.write(newPetnamesStr)
                 return True
             # entry does not exist in the petnames file
@@ -49,7 +49,7 @@ def setPetName(baseDir: str, nickname: str, domain: str,
             return True
 
     # first entry
-    with open(petnamesFilename, 'w') as petnamesFile:
+    with open(petnamesFilename, 'w+') as petnamesFile:
         petnamesFile.write(entry)
     return True
 
diff --git a/posts.py b/posts.py
index dfcfc100f..fdca227b5 100644
--- a/posts.py
+++ b/posts.py
@@ -599,7 +599,7 @@ def addSchedulePost(baseDir: str, nickname: str, domain: str,
                 print('WARN: Failed to write entry to scheduled posts index ' +
                       scheduleIndexFilename + ' ' + str(e))
     else:
-        scheduleFile = open(scheduleIndexFilename, 'w')
+        scheduleFile = open(scheduleIndexFilename, 'w+')
         if scheduleFile:
             scheduleFile.write(indexStr + '\n')
             scheduleFile.close()
@@ -1337,7 +1337,7 @@ def createReportPost(baseDir: str,
         if os.path.isfile(newReportFile):
             continue
         try:
-            with open(newReportFile, 'w') as fp:
+            with open(newReportFile, 'w+') as fp:
                 fp.write(toUrl + '/moderation')
         except BaseException:
             pass
diff --git a/shares.py b/shares.py
index a20fb8055..af300d223 100644
--- a/shares.py
+++ b/shares.py
@@ -181,7 +181,7 @@ def addShare(baseDir: str,
             if not os.path.isfile(newShareFile):
                 nickname = handle.split('@')[0]
                 try:
-                    with open(newShareFile, 'w') as fp:
+                    with open(newShareFile, 'w+') as fp:
                         fp.write(httpPrefix + '://' + domainFull +
                                  '/users/' + nickname + '/tlshares')
                 except BaseException:
diff --git a/theme.py b/theme.py
index 786f49584..c1a323c17 100644
--- a/theme.py
+++ b/theme.py
@@ -105,7 +105,7 @@ def setThemeFromDict(baseDir: str, name: str, themeParams: {}) -> None:
             for paramName, paramValue in themeParams.items():
                 css = setCSSparam(css, paramName, paramValue)
             filename = baseDir + '/' + filename
-            with open(filename, 'w') as cssfile:
+            with open(filename, 'w+') as cssfile:
                 cssfile.write(css)
 
 
@@ -124,11 +124,11 @@ def enableGrayscale(baseDir: str) -> None:
                     css.replace('body, html {',
                                 'body, html {\n    filter: grayscale(100%);')
                 filename = baseDir + '/' + filename
-                with open(filename, 'w') as cssfile:
+                with open(filename, 'w+') as cssfile:
                     cssfile.write(css)
     grayscaleFilename = baseDir + '/accounts/.grayscale'
     if not os.path.isfile(grayscaleFilename):
-        with open(grayscaleFilename, 'w') as grayfile:
+        with open(grayscaleFilename, 'w+') as grayfile:
             grayfile.write(' ')
 
 
@@ -146,7 +146,7 @@ def disableGrayscale(baseDir: str) -> None:
                 css = \
                     css.replace('\n    filter: grayscale(100%);', '')
                 filename = baseDir + '/' + filename
-                with open(filename, 'w') as cssfile:
+                with open(filename, 'w+') as cssfile:
                     cssfile.write(css)
     grayscaleFilename = baseDir + '/accounts/.grayscale'
     if os.path.isfile(grayscaleFilename):
@@ -187,7 +187,7 @@ def setCustomFont(baseDir: str):
                             customFontType + "')")
             css = setCSSparam(css, "*font-family", "'CustomFont'")
             filename = baseDir + '/' + filename
-            with open(filename, 'w') as cssfile:
+            with open(filename, 'w+') as cssfile:
                 cssfile.write(css)
 
 
diff --git a/utils.py b/utils.py
index c53811f26..abdb67be7 100644
--- a/utils.py
+++ b/utils.py
@@ -51,7 +51,7 @@ def saveJson(jsonObject: {}, filename: str) -> bool:
     tries = 0
     while tries < 5:
         try:
-            with open(filename, 'w') as fp:
+            with open(filename, 'w+') as fp:
                 fp.write(json.dumps(jsonObject))
                 return True
         except BaseException:
diff --git a/webinterface.py b/webinterface.py
index 079632c27..4907b1d95 100644
--- a/webinterface.py
+++ b/webinterface.py
@@ -3337,7 +3337,7 @@ def saveIndividualPostAsHtmlToCache(baseDir: str,
         os.mkdir(htmlPostCacheDir)
 
     try:
-        with open(cachedPostFilename, 'w') as fp:
+        with open(cachedPostFilename, 'w+') as fp:
             fp.write(postHtml)
             return True
     except Exception as e: