I am attempting to upgrade to 1.8.1 - I have already done one upgrade on a smaller blog and am now attempting to upgrade on my blog. After I run the installation from previous install, I get the following error:

Altering table «evo_antispam»...

* Added index UNIQUE aspm_string (aspm_string)
An unexpected error has occured!

If this error persits, please report it to the administrator.

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Additional information about this error:

MySQL error!

Duplicate key name 'aspm_string'(Errno=1061)

Your query:

ALTER TABLE evo_antispam ADD UNIQUE aspm_string (aspm_string)

I have tried on both SQL 4 and SQL 5. Any ideas?

UPDATE: Here was the solution, via my personal b2e guru Danny:

Make a backup copy of /install/_db_schema.inc.php, then edit the original and remove line 254: UNIQUE aspm_string (aspm_string)

Save the file, then retry the upgrade on a clean copy of your old db.

This worked perfectly. But make sure you back everything up!!!