Using the new IDE is a headache after another

Sudenly, it refuses to compile a sketch that was working ok, with messages like 'int (the variable)' previously defined here', ridiculous as it is the first and only declaration of the variable.

I must add that I copy and pasted the whole error messages list and it gives the same error for each definition ("redefinition of...").

Sometimes with other sketches, it suddenly gives error: ld returned 5 exit status, and sometimes buy just adding a Serial.println anywhere it is fixed.

Now I restored a copy of a sketch that I saved as soon as it was working, but now it can't be compiled.

I find posts from other users complaining about the latest version. I'm running 1.6.7.

I tried to install previous versions, like 1.6.6, 1.6.0, 1.5.8, some worked without altering the sketch but then it refused to connect to the COM port, even when it was clearly detected in Device Manager as the COM4.

All of this is frustrating.

All of this is frustrating.

Did you have a programming question, or did you just want to frustrate us, too?

I just copied the ino into another PC running 1.6.5 and it compiles like a charm.

Under Programming Questions it says:

Understanding the language, error messages, etc.

Well, I have this problem with error messages that I don't know why they happen.

Well, I have this problem with error messages that I don't know why they happen.

Well, we have this problem with you not posting code or error messages. If we can live with our problem, you can live with your problem.

Now, does it make sense to post the error codes when after going back to 1.6.5 (from 1.6.7) now it compiles the sketch?

Of course, the rule is there ar no rules. Now, even though COM4 appears in Control Panel...Device Manager (I tried to update the driver but it says that it is already updated) and having it selected in the IDE, it doesn't upload any sketch.

rva1945: Now, does it make sense to post the error codes when after going back to 1.6.5 (from 1.6.7) now it compiles the sketch?

It certainly does if you want anyone here to be able to tell you why you got them. Otherwise all I can say is you're doing something wrong. It all works fine for me.

I have the answer to your problem but I didn't type it into this post.

Use the "copy error messages" button on the IDE and let us help you! Use [ code ] tags please.

rva1945: Now, does it make sense to post the error codes when after going back to 1.6.5 (from 1.6.7) now it compiles the sketch?

Yes, of course it does. Your earlier sketch may have used deprecated behaviour. Or, you might have found a bug in the IDE. Now I can hardly submit a bug report on what you have posted so far.

Post minimal code that reproduces the problem (in code tags). Post the error message(s).