I tried to install the game from an external drive, but the installation wizard used disk C's temp folder as ...well, installation folder. My C: is a small SSD filled almost exclusively by system files and I just cannot use it as a temp folder. Is it possible to make the installer use a different disc for unpacking or whatever it is doing with the installation files? Nothing like it has ever happend to me with other games, it is pretty weird and prevents me from installing the game of course.

Best!

You need desperately to either get yourself a larger SSD for your boot drive (optimal), or clear off a lot of space on your C:\ partition (not the best choice, but you should be doing this anyway.) Lots of games use a C:\temp folder for various things--additionally, almost every game will want to park saved games on C:\ these days.

You might check your download folder and clear/move what's in it. Hopefully, you have other drives in your system other than your boot SSD, because if not--where did you plan to install this game?...;)

Also, have you tried running disk cleanup, etc.? How are you installing--through Galaxy, or manually? If you install manually you can tell the game installer to put everything on your external drive--or the *other* drives in your system--without having to install Galaxy to C:\.

klick on the gog symbol -> Properties ->Downloads ->
there is an entry for "installation path for games"..
Change it to whatever you want (my games are on the bigger E drive, on C is my small system SSD like you have)

Like myself he isnt that stupid & you would see it isnt that simple if u actually read properly, I have plenty of HDD space (3x 960GB SSD's & 2x 4TB Hard drives) & I am wanting to install the new Chernobylite game to one of my 960GB SSD's but I currently only have a 256GB M2 drive as my C: drive as I only planned on having Windows installed on it, but it has a few other programs & has less than 40GB of free space remaining on it & the problem we both have (If u read properly) is the GOG installer uses C drive to store all TEMP files on when installing a game so regardless of which drive you are trying to install the game to, if you dont have enough room on C drive for the Temp files of the installer (which are the same size as the game) you cant install the game. So it does NOT matter which drive you set the installer to install the game to as it will always use C drive for the "Temp" files. Obviously we both knew about & did set the installer to install to a drive with more than enough room, otherwise WHY would we even be trying to install a game onto a drive that has nowhere near enough room. The issue here is the GOG installer is horribly stupid & therefor we need to fix it & change where it puts the "Temp" files as in my 25+ years of gaming its the only installer that stupidly does this & that I have ever had an issue with.

Have you tried setting your Windows TEMP-directories to another drive?
See system environment variables....
By changing windows system-variables, so that all windows programs _should_ use another drive/folder.
(old trick with my double/triple-HDD's in 1990's, I'm not sure if this still works?)

...still the same

Research (google) symbolic links (mklink command in a command prompt).
It allows you to redirect any write or read access to a folder to another folder on another drive
(even a network drive).

Workaround:

Use a program such as Advanced Run by NirSoft. Ugh, you'll have to find it yourself, can't post links, I guess. :eyeroll:
In the Advanced Run window:
Add the GOG installer to the "Program to Run:" field.
Set "Run As…" to "Administrator (Force UAC Elevation)" in the dropdown menu. (Advanced Run doesn't have to be run as admin to do this.)
In the "Environment Variables" section, in the dropdown menu, select "Use only the following environment variables (ignore the system variables)"
Click the "Fill Current Environment Strings" button to the right of the dropdown menu. This will fill the text box with variables.
Find "TMP=" and "TEMP=" and change the path on the right of the equals sign to a TEMP folder of your choice. ("D:\TEMP","X:\TEMP", "Path-to-game\TEMP", etc.)
Click Run in the bottom right of the window, the installer should run and use the TEMP folder you specified instead of what you have set.


My issue is that my TEMP folder is set to an 8GiB ram disk and I hate the idea of revisiting the 90's and having to set my %TEMP% and %TMP% to a slow drive, having to restart, install the game, resetting my Temps to the ram disk, then restarting again, ever effing time I want to install a GOG game! PITA!!

So, this should help those who need a workaround.

It's really unbelievable how incompetent this developer group is.

I had a run-in with one of them a few years back on Steam.
That guy was so aggressive, essentially mad cause bad.

Imagine you have like 20 things that all need to evaluate to true,
e.g. initial fight won, met person x, etc...
and you have a condition where you query all those events being fulfilled,
what would you do as a developer? I know what I would do,
give every event a true/false state.

Do you know what they did?
They had a single integer variable that would count up or down if those events were fulfilled.
Of course that bugged out and that was the reason why upon release a certain game feature was not available.

When I asked why they picked an integer I got barked at by one of those failsauce developers.
All I could do is laugh at him but keep explaining to him how what he did was just asking for errors to happen.
He got mad an pulled the "I've been a developer for 7 years and who the fuck are you?" card.
I said truthfully I've been a professional for over 20 years at that time and what he was doing were beginner mistakes.
He totally lost it and started insulting me and eventually even permabanning my from the game's Steam forum.

So like I wrote back then, also truthfully, I met 4 Czech in my life and all 4 of them backstabbed me or were thieves or liars.

Anyone, don't expect too much from those failures.
Seeing that you can't even pick an install location is just in line with my assertion of the quality of those "developers"

Just piggybacking on this to say that I was searching for a solution to the same problem, but for a non GOG game, and this worked. While ideally we would all have big SSDs, some aren't able to afford one or are still running an older system that has a dual SSD HDD (especially for laptops). I was able to change TEMP directories in Windows 10 from the usual folder in C: to a new one I made in D: (my HDD) following your instruction so thank you!

Thanks So Much, It worked ... i was trying to install a game but only had 11gb on my c drive, so with advance run i got it to see the new variables i had already changed in windows , it needed advanced run to make the installer see the new temp directorys , your a legend.

This is NOT an answer.

This worked as well for me. thanks

Thank you brother....your solution for the TEMP installation folder is best ...... i can manage install the big game without trouble.

GOG installer is very badly optimized! I don't have much space od disk C and i can't install large games. Other installers have not TEMP folder. This is very bad because if game need 100gb we need 200gb disc space to install it.