Hi,
Have you tried the following method to delete the extra line break?
1. Go to File > Options > Mail, click Signature button to open the Signatures and Stationary box.
2. Select the signature that you want to modify, and then click Edit.
3. Place the insertion point after the last character in the line, press Delete, and then press Shift + Enter.
4. Repeat Steps 3 for each line of text.
5. Click OK and see if this issue continues.
In addition, we may also try to find the signature file from the following folder and edit the .htm file to see the result:
drive:\Users\<username>\AppData\Roaming\Microsoft\Signatures
Hope this helps.
Regards,
Steve Fan
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