At the heart of NetTools is a LDAP client that includes a decode engine that will decode attributes so that the data can be displayed in a readable format.  The decode engine includes over 80 predefined decode types.  These decodes can be assigned to a specific attribute using four different methods.

These are Static, Dynamic, User Defined, and Manual Override:

The Static assignment are statically defined within NetTools, i.e. WhenChanged is associated to the GTFTIME decode type.  These can be overridden by User Defined and Manual Override assignments. See Static DecodeTypes
While Dynamic will assign the decode type associated to an object based on the schema definition of the attributes. i.e. attributes that are binary and have a fixed length of 32 and guid in the name will automatically be assigned the GUID decode type.
User Defined assigned decode types can be assigned a few different ways in NetTools, from the LDAP Search's Manage Dynamic Attribute Decodes dialog, via the define decode type dialog from the context menu in the Schema Class Browser option, or via the configuration file.  

NetTools.ini Example:     

[AttributeDecodes]
msExchBlockedSendersHash=BIN

The Manual Override option is only available in the LDAP Search option, when specifying the attributes to be displayed, you can also include a Decode Type as an extra parameter of the attribute, this will overridce all other methods and display the attribute using the specified DecodeType i.e. msExchBlockedSendersHash;bin.  This will display the attribute data in a Binary format.

This is the list of Decode Type that are available in NetTools:

    DEFAULT - ASCII
    64DATE - Win32 64bit Date Format
    64TIME - Win32 64bit Date & Time Format, local time
    64TIME_UTC - Win32 64bit Date & Time Format, UTC
    ATTRIBENUM - predefined enumerate
    ATTRIBENUM_NONUM - predefined enumerate only symbolics are displayed
    BASE64 - encode the returned value as Base64    
    BEROID - Basic Encoding Rules (BER) Organization Identifier
    BIN - Binary output
    CERT - Certificates
    COUNT - Returns the number of entries in the attribute
    CRL - Certificate Revocation List
    DNSPROPERTY - DNS Properties entries
    DNSRECORD - DNS entries
    DNSRECORD.DATA - return only the data field
    DNSRECORD.RANK - return only the rank field
    DNSRECORD.SERIAL - return only the serial field
    DNSRECORD.TIMEOUT - return only the timeout field
    DNSRECORD.TIMESTAMP - return only the timestamp field
    DNSRECORD.TTL - return only the ttl field
    DNSRECORD.TYPE - return only the type type field
    DNSRECORD.VERSION - return only the version field
    DSA_SIG - DSA Signature
    FILETIME - Win32 File Date & Time Format
    GTFTIME - Generalized Time Format, local time
    GTFTIME_UTC - Generalized Time Format, UTC
    GMSAPWD - return the full details of the gMSA password
    GMSAPWD.PWD_B - return only the current password in byte hex format
    GMSAPWD.PWD - return only the current password
    GMSAPWD.PPWD_B - return only the previous password in byte hex format
    GMSAPWD.PPWD - return only the previous password
    GMSAPWD.QRY - return the query interval
    GMSAPWD.UCG - return the change interval
    GMSAPWDID - return the full gMSA PasswordID details
    GMSAPWDID.RK - return the gMSA PasswordID Root Key
    GMSAPWDID.SVR - return the gMSA PasswordID server
    GPLINKS - used to display the list of DNs in the gplink attribute
    GUID - Windows COM GUID format
    GUID_LDAP - GUID in LDAP filter format
    GUID_RAW - Hex GUID format
    HEX - Display a number if Hex format
    IP - DWORD IP address in windows order
    IPN - DWORD IP address in network order
    META - Decoder for msDS-ReplAttributeMetaData
    METAP - Decoder for replPropertyMetaData
    METAV - Decoder for msDS-ReplValueMetaData
    MSTRUST - Decoder for msds-TrustForestTrustInfo
    NANOTIME - Display interval based on nano seconds
    NTDS_CONN_OPT - Returns the options for the Options of NTDSConnection
    NTDS_DSA_OPT - Returns the options for the Options of NTDSDSA
    NTDSSSITE_OPT - Returns the options for the Options of NTDS Sites Settings
    PARENTCN - Returns the parent container of the CanonicalName
    PARENTDN - Returns the parent container of the distinguishedName
    PERIOD - Certificate renewal period
    PSMTP - Display primary smtp entry
    PWDSEC - Password secounds
    PX400 - Display primary x400 entry
    PX500 - Display primary x500 entry
    REPL_UTDV - NC Up ToDateness Vectors
    REPS_INFO - Replication neighbours RepsTo and RepsFrom
    RIDPOOL - RID Pool Allocations
    SD - Security Descriptor in SDDL format
    SD_DACL_COUNT - Returns the number of ACE in the DACL
    SD_DACL_EXPCOUNT - Returns the number explicitly assigned ACE in the DACL
    SD_NAME - Returns the resolved names of all the entries in the SD
    SD_NAME_DACL - Returns the resolved names of the DACL entries in the SD
    SD_NAME_GROUP - Return the primary group assigned in the SD
    SD_NAME_OWNER - Returns the resolved name of the owner in the SD
    SD_NAME_SACL - Returns the resolved names of the SACL entries in the SD
    SD_SACL_COUNT - Returns the number of ACE in the SACL
    SD_SACL_EXPCOUNT - Returns the number explicitly assigned ACE in the DACL
    SD_SID - Returns the SID of all entries in the SD
    SD_SID_DACL - Returns the SID of the DACL entries in the SD
    SD_SID_GROUP – Returns the primary group assigned in the SD
    SD_SID_OWNER - Returns the SID of the Owner in the SD
    SD_SID_SACL - Returns the SID of the SACL entries in the SD
    SID - Display Security Identifier in text form
    SID_ABS - Display the absolute name of the SID
    SID_REL - Display the relative name of the SID
    SITE_LINK_OPT - Returns the options for the Options of SiteLink
    SIZE - The size of the data returned
    SMTP - Display only smtp entries
    TRANSPORT_OPT - Returns the options for the Options of transport container
    UNICODE - Return a string in Unicode format, with BOM decode support
    WMITime - Returns the wmi time 
    WMITime_UTC - Returns the utc wmi time
    X400 - Display only x400 entries
    X500 - Display only x500 entries

A debug option exists that will display which Decode Type was used to decode the displayed attributes, the debug information is only displayed in the LDAP Search text output pane.  This debug feature can be enabled by selecting the Enable Decode Debug option in the Attribute Decodes dialog or by added the following entry to the NetTools.ini configuration file.

[SavedOptions]
DebugDecoder=true