A global problem for many gamers when installing a game is an error when unpacking Unarc.dll, because of which the installation is interrupted almost at the initial stage. What kind of failure it is and how to fix it, now let's see.
Unarc.dll returned error code 12: what would it mean?
Let's start by interpreting the failure itself. Since we have exactly the error when unpacking Unarc.dll, it is logical to assume that this is due to decompression of the installation distribution. Partly the way it is.
However, the 12 Unarc.dll error mainly occurs when installing not official distributions that are delivered unpacked, but so-called repacks, created manually and quite often including many additional or unofficial patches, which, in fact, should be unpacked during the installation of the main game files.
Several reasons for the failure
Now let's look at a few specific cases when an error occurs during installation. Unarc.dll in this case has a connection with another dynamic library ISDone.dll. Without going into technical details, we define the two most common situations.
The first is that a CRC Checksum error message is presented in the failure description. What is this talking about? Only that the desired archive is damaged. Incidentally, the reason for the failure is also described: Unarc.dll returned error code 12. How to fix this situation? Yes, very simple. If such a failure occurs, then the archive is simply not uploaded, so you should look for another version of it and download it from another resource. Immediately you need to pay attention to the fact that the archive file can actually be damaged. The solution is the same.
In the second case, the message also lists the Unarc.dll library (error code 12), however, as a result, the system says that decompression failed. This is no longer damage to the archive, as many users think. In fact, everything can be fine with him, only methods of maximum compression were used to reduce its volume (in 7-Zip these are bcj2, ppmd, lzma2, delta, etc. algorithms), the most archived self-extracting SFX archives that require DLLs on unpacking stages, or the latest versions of archiver programs.
Unarc.dll returned error code 12: how to fix it in the simplest way?
Based on the foregoing, let's look at the simplest solution to the problem. Take the standard situation. For example, the repack is packaged with WinRAR version 5, and the user has a fourth installed on the computer. It is clear that with its help decompression of files will be simply impossible, despite the almost identical compression algorithms.
What to do in this case? Yes, just download the latest version of the archiver from the Internet and try again. It should be noted that if, for example, WinRAR does not work, you can try to do the same procedure using 7-Zip. That's all.
We fix ways to install games or other software
But not so simple. The fact is that the failure “Unarc.dll returned error code 12” may also appear in one more commonplace situation. The fact is that some repacks with games and patches, which are “cracked” versions of the original distributions, do not allow unpacking or installation into folders whose names or paths contain Cyrillic characters.
Let us illustrate with an example. Suppose if a user installs a game along the path C: \ Documents \ Games or C: \ Documents \ Games, it simply won’t get there because of the directory names in Cyrillic. As already clear, the problem is partially (if only it really consists in this) is solved by the usual renaming of directories in Latin names.
Increase swap file size
There is another case where a failure occurs with the message "Unarc.dll returned error code 12". This may be due to the paging file being too small or disabling it in the system. It is clear that you need to enable it and adjust the size.
Here you need to be extremely careful, since setting an overestimated or underestimated amount can lead to the complete inoperability of Windows. However, the automatic determination of the file size is also not necessary. Let's do it easier.
To begin, we use the Run menu, called by the Win + R key combination, where we write the sysdm.cpl command, after which we use the options button in the settings window that appears on the Advanced tab and again switch to the Advanced tab in a new window.
In the virtual memory section, click the button for changing settings, and then uncheck the line for automatic settings and specify the size manually. One small piece of advice: in the upper window, where the disks and logical partitions are indicated, it is better not to select the system volume, but to indicate the virtual partition with more space as the place. In addition, we do not change the initial size, but here we specify as the maximum one that is equal to the volume of the "RAM". For example, a user has 4 GB memory sticks installed. The corresponding size will be 4096 MB. Remember that 1 GB contains 1024 MB, not a thousand, as some people think. Now it remains to press the button to set the size and save the changes, after which it is desirable to reboot the system (this is not a prerequisite, such a procedure, say, is strongly recommended for execution).
Note: you can access the page file settings from the standard "Control Panel" in the system properties section, however, entering the command will be a faster way.
Checking RAM
Finally, another problem related to the failure, and the message indicates that Unarc.dll returned error code 12, may be due to incorrect operation of RAM (too much and unreasonable load, physical damage, etc.) . Although this situation is not common, it cannot be discounted.
In this case, the situation with stationary terminals looks simpler. You just need to remove all the memory strips from the slots on the "motherboard", then insert them alternately, after which each time try again to install or unpack.
But before that, it is imperative to check the "RAM". You can use the built-in Windows tools for this. The verification tool is selected from the administration section in the "Control Panel".
However, as practice shows, it is better to use the specialized utility Memtest86 +, which must first be downloaded from the Internet, and then use it to create a boot disk, and only then start from it. This program works more efficiently than the native Windows utility.
When the scan is over, it will be possible to find out exactly where the failure occurred, and whether it occurred at all. As already clear, if the planks have become unusable, they will have to be replaced.
With laptops, the situation is somewhat more complicated, because opening them yourself, and even if they are under warranty, certainly not worth it. There is only one way out: contact a service center. You can, of course, try to fix the problem yourself. But this, as they say, is at your own peril and risk.
Should I download failed libraries from the Internet?
Finally, a few words about another solution that some, so to say, “experts” propose. They recommend simply downloading the Unarc.dll and ISDone.dll files from the Internet and copying them to the appropriate location on the hard drive. We must say right away: it’s not worth doing such stupid things. The maximum that can be achieved is only to change the error code, for example, by 7 or 1. But the above recommendations fix the problem by 99%. If all else fails, reinstalling Windows cannot be avoided because the problem can be much deeper.
Conclusion
As you can see, the proposed solutions to the problem are quite simple and understandable. However, the problems associated with viruses were not considered here. Firstly, they are extremely rare, and secondly, any self-respecting user himself must know how to test the system for threats and eliminate them.