diff --git a/td/telegram/MessagesManager.cpp b/td/telegram/MessagesManager.cpp
index 419cabdb5..3b3db6979 100644
--- a/td/telegram/MessagesManager.cpp
+++ b/td/telegram/MessagesManager.cpp
@@ -11164,7 +11164,11 @@ void MessagesManager::unload_dialog(DialogId dialog_id) {
     LOG(ERROR) << "Unknown dialog " << dialog_id;
     return;
   }
-  CHECK(d->has_unload_timeout);
+
+  if (!d->has_unload_timeout) {
+    // possible right after the dialog was opened
+    return;
+  }
 
   if (!is_message_unload_enabled()) {
     // just in case
@@ -14918,7 +14922,13 @@ void MessagesManager::on_get_dialogs(FolderId folder_id, vector<tl_object_ptr<te
         }
       }
       for (auto dialog_id : old_pinned_dialog_ids) {
-        if (set_dialog_is_pinned(dialog_id, false)) {
+        Dialog *d = get_dialog_force(dialog_id);
+        if (d == nullptr) {
+          LOG(ERROR) << "Failed to find " << dialog_id << " to unpin in " << folder_id;
+          force_create_dialog(dialog_id, "from_pinned_dialog_list", true);
+          d = get_dialog_force(dialog_id);
+        }
+        if (d != nullptr && set_dialog_is_pinned(DialogListId(folder_id), d, false)) {
           are_pinned_dialogs_saved = true;
         }
       }
@@ -19129,7 +19139,15 @@ Status MessagesManager::set_pinned_dialogs(DialogListId dialog_list_id, vector<D
     set_dialog_is_pinned(dialog_id, true);
   }
   for (auto dialog_id : old_pinned_dialog_ids) {
-    set_dialog_is_pinned(dialog_id, false);
+    Dialog *d = get_dialog_force(dialog_id);
+    if (d == nullptr) {
+      LOG(ERROR) << "Failed to find " << dialog_id << " to unpin in " << dialog_list_id;
+      force_create_dialog(dialog_id, "set_pinned_dialogs", true);
+      d = get_dialog_force(dialog_id);
+    }
+    if (d != nullptr) {
+      set_dialog_is_pinned(dialog_list_id, d, false);
+    }
   }
 
   if (server_old_dialog_ids != server_new_dialog_ids) {
@@ -34081,6 +34099,7 @@ MessageId MessagesManager::get_message_id_by_random_id(Dialog *d, int64 random_i
 void MessagesManager::force_create_dialog(DialogId dialog_id, const char *source, bool expect_no_access,
                                           bool force_update_dialog_pos) {
   LOG_CHECK(dialog_id.is_valid()) << source;
+  LOG_CHECK(is_inited_) << dialog_id << ' ' << source << ' ' << expect_no_access << ' ' << force_update_dialog_pos;
   Dialog *d = get_dialog_force(dialog_id);
   if (d == nullptr) {
     LOG(INFO) << "Force create " << dialog_id << " from " << source;
@@ -34171,6 +34190,7 @@ MessagesManager::Dialog *MessagesManager::add_dialog(DialogId dialog_id) {
 
 MessagesManager::Dialog *MessagesManager::add_new_dialog(unique_ptr<Dialog> &&d, bool is_loaded_from_database) {
   auto dialog_id = d->dialog_id;
+  LOG_CHECK(is_inited_) << dialog_id << ' ' << is_loaded_from_database;
   switch (dialog_id.get_type()) {
     case DialogType::User:
       if (dialog_id == get_my_dialog_id() && d->last_read_inbox_message_id == MessageId::max() &&
@@ -34903,8 +34923,9 @@ bool MessagesManager::set_dialog_order(Dialog *d, int64 new_order, bool need_sen
   }
 
   auto folder_ptr = get_dialog_folder(d->folder_id);
-  LOG_CHECK(folder_ptr != nullptr) << dialog_id << ' ' << d->folder_id << ' ' << is_loaded_from_database << ' '
-                                   << source;
+  LOG_CHECK(folder_ptr != nullptr) << is_inited_ << ' ' << G()->close_flag() << ' ' << dialog_id << ' ' << d->folder_id
+                                   << ' ' << is_loaded_from_database << ' ' << td_->auth_manager_->is_authorized()
+                                   << ' ' << td_->auth_manager_->was_authorized() << ' ' << source;
   auto &folder = *folder_ptr;
   if (old_date == new_date) {
     if (new_order == DEFAULT_ORDER) {
diff --git a/tdutils/td/utils/port/FileFd.cpp b/tdutils/td/utils/port/FileFd.cpp
index d5c0db9dc..8ee8c4a40 100644
--- a/tdutils/td/utils/port/FileFd.cpp
+++ b/tdutils/td/utils/port/FileFd.cpp
@@ -36,6 +36,8 @@
 #include <sys/types.h>
 #include <sys/uio.h>
 #include <unistd.h>
+#else
+#include <limits>
 #endif
 
 #if TD_PORT_WINDOWS && defined(WIN32_LEAN_AND_MEAN)
@@ -254,7 +256,9 @@ Result<size_t> FileFd::write(Slice slice) {
   BOOL success = WriteFile(native_fd, slice.data(), narrow_cast<DWORD>(slice.size()), &bytes_written, nullptr);
 #endif
   if (success) {
-    return narrow_cast<size_t>(bytes_written);
+    auto result = narrow_cast<size_t>(bytes_written);
+    CHECK(result <= slice.size());
+    return result;
   }
   return OS_ERROR(PSLICE() << "Write to " << get_native_fd() << " has failed");
 }
@@ -266,14 +270,29 @@ Result<size_t> FileFd::writev(Span<IoSlice> slices) {
   auto bytes_written = detail::skip_eintr([&] { return ::writev(native_fd, slices.begin(), slices_size); });
   bool success = bytes_written >= 0;
   if (success) {
-    return narrow_cast<size_t>(bytes_written);
+    auto result = narrow_cast<size_t>(bytes_written);
+    auto left = result;
+    for (const auto &slice : slices) {
+      if (left <= slice.iov_len) {
+        return result;
+      }
+      left -= slice.iov_len;
+    }
+    UNREACHABLE();
   }
   return OS_ERROR(PSLICE() << "Writev to " << get_native_fd() << " has failed");
 #else
   size_t res = 0;
-  for (auto slice : slices) {
+  for (const auto &slice : slices) {
+    if (slice.size() > std::numeric_limits<size_t>::max() - res) {
+      break;
+    }
     TRY_RESULT(size, write(slice));
     res += size;
+    if (size != slice.size()) {
+      CHECK(size < slice.size());
+      break;
+    }
   }
   return res;
 #endif
@@ -305,7 +324,9 @@ Result<size_t> FileFd::read(MutableSlice slice) {
     if (is_eof) {
       get_poll_info().clear_flags(PollFlags::Read());
     }
-    return static_cast<size_t>(bytes_read);
+    auto result = narrow_cast<size_t>(bytes_read);
+    CHECK(result <= slice.size());
+    return result;
   }
   return OS_ERROR(PSLICE() << "Read from " << get_native_fd() << " has failed");
 }
@@ -329,7 +350,9 @@ Result<size_t> FileFd::pwrite(Slice slice, int64 offset) {
   BOOL success = WriteFile(native_fd, slice.data(), narrow_cast<DWORD>(slice.size()), &bytes_written, &overlapped);
 #endif
   if (success) {
-    return narrow_cast<size_t>(bytes_written);
+    auto result = narrow_cast<size_t>(bytes_written);
+    CHECK(result <= slice.size());
+    return result;
   }
   return OS_ERROR(PSLICE() << "Pwrite to " << get_native_fd() << " at offset " << offset << " has failed");
 }
@@ -352,7 +375,9 @@ Result<size_t> FileFd::pread(MutableSlice slice, int64 offset) const {
   BOOL success = ReadFile(native_fd, slice.data(), narrow_cast<DWORD>(slice.size()), &bytes_read, &overlapped);
 #endif
   if (success) {
-    return narrow_cast<size_t>(bytes_read);
+    auto result = narrow_cast<size_t>(bytes_read);
+    CHECK(result <= slice.size());
+    return result;
   }
   return OS_ERROR(PSLICE() << "Pread from " << get_native_fd() << " at offset " << offset << " has failed");
 }
diff --git a/tdutils/td/utils/port/FromApp.h b/tdutils/td/utils/port/FromApp.h
index bab7324a8..71cdfb9bb 100644
--- a/tdutils/td/utils/port/FromApp.h
+++ b/tdutils/td/utils/port/FromApp.h
@@ -76,11 +76,15 @@ inline BOOL DeleteFileFromAppW(_In_ LPCWSTR lpFileName) {
 }
 
 inline BOOL MoveFileExFromAppW(_In_ LPCWSTR lpExistingFileName, _In_ LPCWSTR lpNewFileName, _In_ DWORD dwFlags) {
-  auto func = get_from_app_function<4>("MoveFileFromAppW", &MoveFileEx);
-  if (func != &MoveFileEx && (dwFlags & MOVEFILE_REPLACE_EXISTING) != 0) {
+  auto func = get_from_app_function<4>("MoveFileFromAppW", &MoveFile);
+  if (func == &MoveFile || (dwFlags & ~MOVEFILE_REPLACE_EXISTING) != 0) {
+    // if can't find MoveFileFromAppW or have unsupported flags, call MoveFileEx directly
+    return MoveFileEx(lpExistingFileName, lpNewFileName, dwFlags);
+  }
+  if ((dwFlags & MOVEFILE_REPLACE_EXISTING) != 0) {
     td::DeleteFileFromAppW(lpNewFileName);
   }
-  return func(lpExistingFileName, lpNewFileName, dwFlags);
+  return func(lpExistingFileName, lpNewFileName);
 }
 
 inline HANDLE FindFirstFileExFromAppW(_In_ LPCWSTR lpFileName, _In_ FINDEX_INFO_LEVELS fInfoLevelId,
diff --git a/tdutils/td/utils/port/IoSlice.h b/tdutils/td/utils/port/IoSlice.h
index f1d356dd1..47fa230d8 100644
--- a/tdutils/td/utils/port/IoSlice.h
+++ b/tdutils/td/utils/port/IoSlice.h
@@ -25,7 +25,7 @@ inline IoSlice as_io_slice(Slice slice) {
   return res;
 }
 
-inline Slice as_slice(const IoSlice io_slice) {
+inline Slice as_slice(const IoSlice &io_slice) {
   return Slice(static_cast<const char *>(io_slice.iov_base), io_slice.iov_len);
 }
 
diff --git a/tdutils/td/utils/port/SocketFd.cpp b/tdutils/td/utils/port/SocketFd.cpp
index 05e6aee4b..83d418a0c 100644
--- a/tdutils/td/utils/port/SocketFd.cpp
+++ b/tdutils/td/utils/port/SocketFd.cpp
@@ -18,6 +18,8 @@
 #include "td/utils/port/detail/Iocp.h"
 #include "td/utils/SpinLock.h"
 #include "td/utils/VectorQueue.h"
+
+#include <limits>
 #endif
 
 #if TD_PORT_POSIX
@@ -98,7 +100,9 @@ class SocketFdImpl : private Iocp::Callback {
   Result<size_t> writev(Span<IoSlice> slices) {
     size_t total_size = 0;
     for (auto io_slice : slices) {
-      total_size += as_slice(io_slice).size();
+      auto size = as_slice(io_slice).size();
+      CHECK(size <= std::numeric_limits<size_t>::max() - total_size);
+      total_size += size;
     }
 
     auto left_size = total_size;
@@ -399,7 +403,19 @@ class SocketFdImpl {
       return ::writev(native_fd, slices.begin(), slices_size);
 #endif
     });
-    return write_finish(write_res);
+    if (write_res >= 0) {
+      auto result = narrow_cast<size_t>(write_res);
+      auto left = result;
+      for (const auto &slice : slices) {
+        if (left <= slice.iov_len) {
+          return result;
+        }
+        left -= slice.iov_len;
+      }
+      LOG(FATAL) << "Receive " << result << " as writev response, but tried to write only " << result - left
+                 << " bytes";
+    }
+    return write_finish();
   }
 
   Result<size_t> write(Slice slice) {
@@ -412,15 +428,17 @@ class SocketFdImpl {
           ::write(native_fd, slice.begin(), slice.size());
 #endif
     });
-    return write_finish(write_res);
+    if (write_res >= 0) {
+      auto result = narrow_cast<size_t>(write_res);
+      LOG_CHECK(result <= slice.size()) << "Receive " << result << " as write response, but tried to write only "
+                                        << slice.size() << " bytes";
+      return result;
+    }
+    return write_finish();
   }
 
-  Result<size_t> write_finish(ssize_t write_res) {
+  Result<size_t> write_finish() {
     auto write_errno = errno;
-    if (write_res >= 0) {
-      return narrow_cast<size_t>(write_res);
-    }
-
     if (write_errno == EAGAIN
 #if EAGAIN != EWOULDBLOCK
         || write_errno == EWOULDBLOCK
@@ -468,7 +486,9 @@ class SocketFdImpl {
         get_poll_info().clear_flags(PollFlags::Read());
         get_poll_info().add_flags(PollFlags::Close());
       }
-      return narrow_cast<size_t>(read_res);
+      auto result = narrow_cast<size_t>(read_res);
+      CHECK(result <= slice.size());
+      return result;
     }
     if (read_errno == EAGAIN
 #if EAGAIN != EWOULDBLOCK