Error: 18780, Severity: 16, You have specified a value for the @dts_package_password parameter. You must also specify a value for the @dts_package_name parameter.
Error: 18781, Severity: 16, The value specified for the @backupdevicetype parameter is not valid. The value must be ‘logical’, ‘disk’, or ‘tape’.
Error: 18782, Severity: 16, Could not locate backup header information for database ‘%s’ in the specified backup device. Specify a backup device that contains a backup of the Publisher database.
Error: 18783, Severity: 16, The subscription setup script path has been truncated, because the snapshot folder directory path is too long. Reconfigure the Distributor to use a shorter path for this Publisher, and then retry the operation.

Error: 18784, Severity: 16, The alternate snapshot folder path generated by replication has been truncated. Reconfigure the publication to use a shorter alternate snapshot folder path, and then retry the operation.
Error: 18786, Severity: 16, The specified publication does not allow subscriptions to be initialized from a backup. To allow initialization from a backup, use sp_changepublication: set ‘allow_initialize_from_backup’ to ‘true’.
Error: 18787, Severity: 16, Snapshot publications cannot use the option to initialize a subscription from a backup. This option is only supported for transactional publications.
Error: 18790, Severity: 16, Cannot enable the option to initialize a subscription from a backup. This is not supported for non-SQL Server Publishers; it is only supported for transactional publications from SQL Server Publishers.

Error: 18795, Severity: 16, The valid new types of a log based indexed view article are ‘indexed view logbased’, ‘indexed view logbased manualfilter’, ‘indexed view logbased manualview’, and ‘indexed view logbased manualboth’ only.
Error: 18796, Severity: 16, The valid new types of a log based table article are ‘logbased’, ‘logbased manualfilter’, ‘logbased manualview’, and ‘logbased manualboth’ only.
Error: 18799, Severity: 16, Only users who are members of the following roles can perform this operation: sysadmin fixed server role; dbowner or dbcreator fixed database role in the current database.
Error: 18801, Severity: 16, Unable to allocate memory for replication schema version node.
Error: 18802, Severity: 16, Cannot insert a new schema change into the systranschemas system table. HRESULT = ‘0x%x’. If the problem persists, contact Customer Support Services.
Error: 18803, Severity: 16, The topic %.*ls is not a supported help topic. To see the list of supported topics, execute the stored procedure sp_replhelp N’helptopics’.
Error: 18804, Severity: 16, Peer-to-peer replication has been enabled, and the Log Reader Agent was unable to find an Extended-Originator-Record (EOR) for a transaction that did not originate at this server. Contact Customer Support Services.
Error: 18805, Severity: 16, The Log-Scan Process failed to construct a replicated command from log sequence number (LSN) {%08lx:%08lx:%04lx}. Back up the publication database and contact Customer Support Services.
Error: 18806, Severity: 16, Cannot initialize the replication resource. Ensure that SQL Server has sufficient memory. If the problem persists, restart SQL Server.
Error: 18807, Severity: 16, Cannot find an object ID for the replication system table ‘%s’. Verify that the system table exists and is accessible by querying it directly. If it does exist, stop and restart the Log Reader Agent; if it does not exist, drop and reconfigure replication.
Error: 18808, Severity: 16, Article information is not valid. Stop the Log Reader Agent, execute the stored procedure sp_replflush, and then restart the Log Reader Agent.
Error: 18809, Severity: 16, END_UPDATE log record {%08lx:%08lx:%04lx} encountered without matching BEGIN_UPDATE.

This is applicable on below versions of SQL Server

SQL Server 2005
SQL Server 2008 R2
SQL Server 2012
SQL Server 2014

Hope this was helpful.

Thanks,
SQLServerF1 Team
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