Error message: "The object reference was not set to an instance of an object" - how to fix the problem

If the above steps dont solve the problem, you should check the Windows Registry for the default settings for the e-mail program.

1. Open the registry editor using the key combination [Windows] + [R] by entering "regedit" there and confirming with "OK".
2. In the top bar, add the path "HKEY_LOCAL_MACHINESOFTWAREClientsMail" without quotation marks and confirm with [Enter].
3. To the right of the "(Standard)" key is the name of the standard e-mail program. If this is not the name you want, you can change it by editing the key.
4. To enter the correct name, go to "HKEY_LOCAL_MACHINESOFTWAREWOW6432nodeClientsMail" via the top bar. The other possible e-mail programs are listed here.
5. Double click on the key of the program you want to set as default and copy the value displayed there.
6. Then call up "HKEY_LOCAL_MACHINESOFTWAREClientsMail" again, double-click on the "(Default)" key and paste the value you just copied.

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