Mail crashes

When opening Mail on my iMac it crashes and close the application. An error report is generated, however, I am not able to understand what is wrong with the Mail app.

Anybody who know how I can get to my mail account and make the program stay open??

Mail works on my iPad and iPhone

This is the first part of the report

Process: Mail [1492]

Path: /Applications/Mail.app/Contents/MacOS/Mail

Identifier: com.apple.mail

Version: 11.5 (3445.9.1)

Build Info: Mail-3445009001000000~1

Code Type: X86-64 (Native)

Parent Process: ??? [1]

Responsible: Mail [1492]

User ID: 501

Date/Time: 2018-09-09 16:29:17.925 +0200

OS Version: Mac OS X 10.13.6 (17G65)

Report Version: 12

Anonymous UUID: A3025AA0-A72F-2C46-2644-3124E31BFD28

Sleep/Wake UUID: 0695F317-7AC2-4BFD-96A9-31B18C299A34

Time Awake Since Boot: 11000 seconds

Time Since Wake: 1300 seconds

System Integrity Protection: enabled

Crashed Thread: 1 Dispatch queue: com.apple.root.default-qos

Exception Type: EXC_CRASH (SIGABRT)

Exception Codes: 0x0000000000000000, 0x0000000000000000

Exception Note: EXC_CORPSE_NOTIFY

Application Specific Information:

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSCFConstantString substringToIndex:]: Index 36 out of bounds; string length 0'

terminating with uncaught exception of type NSException

abort() called