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The goal was to find all branch currents. I solved it by hand and then tried to compare the result's validity with the LTspice. But as you can see, they don't match at all! I added a 0V source in front of R2 to get F1(CCCS) working. In LTspice a CCCS doesn't work if the current doesn't come from a source. F1 : CCCS H1: CCVS

Rajiv Das
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    For F1 you should have V2 -2 instead of only 2. And for H1 ---> V1 -4 – G36 Jun 28 '23 at 18:31
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    Does this answer your question? [Help me to solve this question using mesh analysis](https://electronics.stackexchange.com/questions/671337/help-me-to-solve-this-question-using-mesh-analysis). You should have edited the linked question rather than begin a new question on exactly the same topic. – Andy aka Jun 29 '23 at 07:43

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(Realized after I posted this that @G36 had already indicated the sign error in a comment. Leaving it up because I went to the trouble to make screenshots, and because he didn't say why the sign change was necessary)

As pointed out by @Andy aka, your hand calculations are correct. The issue is very simple: The sign convention for current flow that LTspice uses.

The clue is here when you mouse over a voltage source to show its current after a simulation: enter image description here

Note the cursor arrow is from left to right, which is the opposite of the way you have defined "ib" in your hand-drawn schematic.

This is the same for all voltage sources in LTspice, so if you add a negative to the gain of H1 and F1, everything simulates correctly! enter image description here

Brandon Hill
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    Seems like it is high time to stop using LTspice. How would I know when to set a -ve gain and when to not? – Rajiv Das Jun 29 '23 at 05:46
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    The convention that LTspice uses is consistent. You will only need to invert the sign of the gain when the LTspice convention doesn't match whatever is in your assignment. I wouldn't jump ship too quickly over a sign convention issue. I think you will find that the choice of sign convention is just something to be careful of in any piece of software or any assignment. Teachers, textbooks, and software all vary in how they choose to assign sign to direction. Even the generally accepted idea of positive current flow is actually opposite to the actual flow of electrons. Its all just convention. – Brandon Hill Jun 29 '23 at 15:14