I think I had simlar issues before due to the way Episerver handle the versions and updates.
I think I fixed it by just deleting any objects that throw that error or editng the script a commenting out the offending line.
I had to take similar actions.
Firstly it tried to create a stored procedure that already existed so I removed that [netConvertCategoryPropertyForPageType] ,
and then the same on a unique index on TblCategory (IDX_tblCategory_Unique).
That seems to have solved it for me.
After upgrading the following packages:
EPiServer.CMS.Core 11.7.1 -> 11.11.3
EPiServer.CMS.UI.Core 11.4.5 -> 11.19.2
EPiServer.CMS 11.7.1 -> 11.11.3
EPiServer.CMS.TinyMce 2.2.0 -> 2.8.0
EPiServer.CMS.UI.Sources 11.4.5 -> 11.19.2
EPiServer.Forms 4.11.0 -> 4.24.3
EPiServer.GoogleAnalytics 2.1.1 -> 2.2.1
EPiServer.Labs.LanguageManager 3.1.2 -> 3.3.1
EPiServer.Social 2.3.0 -> 3.0.2
BVN.404Handler 11.1.11 -> 11.2.3
Episerver.Framework 11.7.1 -> 11.11.3
And maybe some more as dependencies.
I'm getting: System.Data.SqlClient.SqlException (0x80131904): There is already an object named 'netConvertCategoryPropertyForPageType' in the database.
vid System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapClo