Autotake eD2k Links only during runtime
This option only associates the eD2k link format when eMule is actually up. When eMule is closed the association is deleted to allow uninterrupted working of other eD2k clients.
Use Credit System (Reward Uploaders)
It is strongly recommended to leave the Credit System turned on as it will deter leechers from harming the network.
Open/close ports on Win XP firewall when starting/exiting eMule
eMule is able to automatically open its needed ports in the internal Windows XP firewall. This setting will further increase security by not keeping the ports open after eMule is closed and to open them up again when it is started. This setting is only available in Windows XP and only for the internal firewall, not any third party products. This option does not work correctly in the current Win XP Sp2 RC releases.
Filter server and client LAN IPs
Sources containing IPs of the private IP classes A (10.0.0.0 - 10.255.255.255), B (172.16.0.0 - 172.31.255.255), C (192.168.0.0 - 192.168.255.255), local host (127.0.0.0 to 127.255.255.254) and all IPs starting with null (0.x.x.x) are not valid in the internet. Such sources received by client to client source exchange or by servers are dropped when this filter is activated.
Note: Running eMule in a local network (LAN) requires this option be turned off or eMule will not be able to find any sources in this network.
Show more controls (advanced mode controls)
This options activates even more functions in eMule which are usually not needed for running it.
Disable A4AF checks to save CPU
This will turn off any source handling as described in the Advanced Source Handling chapter. Only when a download is canceled, potential A4AF sources are redistributed according to the priorities.
Hostname for own eD2k Links
In the shared files main tab eD2k links with the current IP as source can be created. Entering a hostname in this filed allows to create such links with the hostname instead of the IP. The advantage of this link is that it is still valid should your IP change.
Disable downloading from PeerCache
PeerCache is a system that will cache downloads in a completely anonymous way at the ISP level. This will decrease the amount of traffic an ISP has to cope with by buffering parts of downloads in its own system and so also providing better download speeds for the users. ISPs have to support this feature to be effective.
Create new part files as sparse (NTFS only)
Sparse files are an NTFS (NT File System) feature, thus only available when the harddisk is formatted using NTFS. As the single parts or chunks of a file are not necessarily downloaded in the correct sequence, the space between the already-downloaded parts are filled with zeros. Usually these zeros would eat up space on the harddisk the same way as if they were actually filled with useful data. To prevent this the NTFS sparse file support does not store the zeros but keeps track of where the single parts actually belong in the file. This reduces the diskspace overhead needed during a download. When the file is finished NTFS takes care of the correct sequence of all the parts.
The size of eMule's temporary download files increases dynamically on demand. The Check Diskspace option ensures that the current downloads can be entirely downloaded and completed. Downloads which are too big for the current free disk space get paused so that other downloads can be completed. When free disk space increases the paused downloads will restart automatically.
Safe .met / .dat file writing
On newer operating systems using NTFS as file system there is usually no need to change this option. If downloads are reproducibly lost on crashes or eMule shut downs the safer method should be tried. Depending on the hardware used, this option may notably increase disk activity / system load or prolong eMule's shut down!
Extract meta data
This feature controls how meta data (bitrate, resolution, codec etc) is extracted from finished/newly hashed files. This data is then published to servers or the Kademlia network. In the search options it can be specified e.g. to search only for mp3 files with a bitrate of at least 128 kb/s.
Save logs to disk
The output of the two log windows of the Server tab - Log and Debug - can be saved to disk by turning on the corresponding option. They will be save as eMule.log or eMule_Debug.log in eMule's installation folder.
If Verbose mode is turned on an additional Debug tab is displayed in the Server window. The information shown therein are for development only and no additional support on these will be provided. This option causes a greater CPU and memory load. Not recommended for normal operation. The Log Level option controls which log messages are shown. Level 5 means all verbose messages whereas level 1 shows only the most important one.
Upload Speed Sense (USS)
USS is a function to monitor the ping times of the connection and to automatically adjust eMule's upload according to this ping value. This ensures that the connection never cloggs and will try to keep surfing and online gaming fluid. It is recommended to keep the default settings.
Please note: It is recommended to set an upload limit in the connection preferences even if USS is enabled. USS will respect the manually set upload limit and never go above that, and knowing the absolute max will help it reach a more stable upload speed.
Sharing eMule with other computer users
This option allows you to change how eMule should behave on a multi-user system. The main difference is that either all users have the same downloads and settings or each user has its own.
It is important to notice that if you change this setting, eMule will use another directory for its configuration files, which will result in a "loss" of all settings. This means you will also not see your downloads or shared files, because eMule is using different default directories. But of course you can always adjust them in the directory dialog. You can also always revert this option and all your old setting will be still there.
You need to restart eMule if you change this option to see any effect.