diff --git a/README.md b/README.md
index a8d17afd..db5f9bbc 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,10 @@
 [![OpenDTU Build](https://github.com/tbnobody/OpenDTU/actions/workflows/build.yml/badge.svg)](https://github.com/tbnobody/OpenDTU/actions/workflows/build.yml)
 [![cpplint](https://github.com/tbnobody/OpenDTU/actions/workflows/cpplint.yml/badge.svg)](https://github.com/tbnobody/OpenDTU/actions/workflows/cpplint.yml)
 
+## !! IMPORTANT UPGRADE NOTES !!
+
+If you are upgrading from a version before 15.03.2023 you have to upgrade the partition table of the ESP32. Please follow the [this](docs/UpgradePartition.md) documentation!
+
 ## Background
 This project was started from [this](https://www.mikrocontroller.net/topic/525778) discussion (Mikrocontroller.net).
 It was the goal to replace the original Hoymiles DTU (Telemetry Gateway) with their cloud access. With a lot of reverse engineering the Hoymiles protocol was decrypted and analyzed.
diff --git a/docs/UpgradePartition.md b/docs/UpgradePartition.md
new file mode 100644
index 00000000..dce998ae
--- /dev/null
+++ b/docs/UpgradePartition.md
@@ -0,0 +1,24 @@
+# Upgrade Partition
+
+To be able to install further updates you have to update the partition table of the ESP32. Doing so will **erase** all configuration data. Over The Air update using the web interface is **NOT** possible!
+
+**So make sure you export a backup of your configuration files before continuing.**
+
+There are several possibilities to update the partition table:
+- Using Visual Studio Code or PlatformIO CLI
+
+   If you have already used Visual Studio Code or the `platformio` command you can use it again to install the latest version. The partition table is upgraded automatically.
+
+- Any kind of flash interface
+
+   If you like to use any kind of flash interface like `esptool.py`, Espressif Flash Download Tool, ESP_Flasher or esptool-js you have to make sure to upload **ALL** provided .bin files. It is important to enter the correct target addresses.
+
+   | Address  | File                   |
+   | ---------| ---------------------- |
+   | 0x1000   | bootloader.bin         |
+   | 0x8000   | partitions.bin         |
+   | 0xe000   | boot_app0.bin          |
+   | 0x10000  | opendtu-*.bin          |
+
+
+After upgrading the ESP32 will open the intergrated access point (AP) again. Just connect to it using the default password ("openDTU42"). If you are connected, just visit http://192.168.4.1 and enter the "Configuration Management". Recover the previously backuped config files.
\ No newline at end of file
diff --git a/partitions_custom.csv b/partitions_custom.csv
index abf9a200..d18ab18f 100644
--- a/partitions_custom.csv
+++ b/partitions_custom.csv
@@ -1,6 +1,6 @@
-# Name,   Type, SubType, Offset,  Size, Flags
-nvs,      data, nvs,     0x9000,  0x5000,
-otadata,  data, ota,     0xe000,  0x2000,
-app0,     app,  ota_0,   0x10000, 0x180000,
-app1,     app,  ota_1,   0x190000,0x180000,
-spiffs,   data, spiffs,           ,0x50000
\ No newline at end of file
+# Name,   Type, SubType, Offset,   Size,    Flags
+nvs,      data, nvs,     0x9000,   0x5000,
+otadata,  data, ota,     0xe000,   0x2000,
+app0,     app,  ota_0,   0x10000,  0x1E0000,
+app1,     app,  ota_1,   0x1F0000, 0x1E0000,
+spiffs,   data, spiffs,  0x3D0000, 0x30000,
\ No newline at end of file