Use www.mapleprimes.com/recent

This is the best way to view just the titles.

**edit added** ah yes, nevermind, I see you found it by clicking on the Recent button which I've never noticed.  I generally just type in the location above in the address bar and go directly to the list.  I rarely ever use the mapleprimes home page if ever. 

[seq(add(a[ .. i]), i = 1 .. nops(a))]
                         [ 1, 3, 6, 10]

Maple 2016.1a is now available at the Maplesoft website that fixes this issue.

Ok finally I managed to reproduce what you might be experiencing.

The issue has to do with using the greek letter Pi and then using the wordPi.

plot(cos(x),x=0..Pi)

going back deleting Pi and replacing it with ∏ or 2*∏ then again going back deleting and replacing it with Pi.

That's what I've been able to find. 

My x^2 issue I found was just bad syntax there is no problem there.  Your plot issue was just you putting the wrong variable to the range.

I can not replicate any errors you produce.  Have been able to replicate the errors on another worksheet?  Are you using windows 10?  or  Mac?

It seems that error only comes up when you use the greek letter from the pallete and used without the multiplication sign. 

After which no matter what you do the error won't go away until you restart and use the pallete symbol with a space as multiplication again.

You aren't explaining EXACTLY what you are doing.  I think you are missing some things in explaining what you are doing. 

The only lines causing errors are the ones that look like this after copying to notepad

(∫)[0]^(Pi)sin(x) ⅆx;

(∫)[0]^(2 )(x)^(2) ⅆx

Your other lines that execute properly look proper when copied to notepad.  I can only think you are doing some kind of deleting or adding a space or something in the wrong spot however which I can not duplicate.

After re-installing.  I am having no luck (or good luck as the case may be) trying to recreate the errors you experience. 

I can not, no matter what I do get the errors you see.  I am trying to find out what you are doing.

Only after downloading your Bad Maple worksheet did I start exhibiting these problems.  I tried to restore my computer to earlier times and I've done it before but now after a restart (restarted funny) I have no restore points - and I should. 

I suspect there exists a virus in your file. 

I tried exactly what you did again in 2016.1 and did NOT get the errors you see.

Regarding your claim to know the proper syntax with

plot(t,x=0..2) let me remind you that YES that is BAD syntax.  With that you WILL get the errorWarning, expecting only range variable x in expression t to be plotted but found name t

That error is received in both 2016.1 and in Maple 18.  Again bad plot syntax as I correctly suggested earlier.  Considering you most likely mistakenly forgot about that bad syntax you presented I could not no matter how hard I tried to get the error you presented.

Your bugs in parsing resource can not be found.  It is most likely some combination of lines you deleted and re-executed after which caused the error.  Maple integrates no problems for me with Pi and pi in the definite integrals.  As with differentiation, it is carried out with no problems. 

int(x^2,x=0..2) returns the correct answer.

using the graphing interface I tried multiple times to replicate your error. 

Let me ask if you have been able to repeat your errors on a new sheet?

I suspect you have done something to create that error.  It does not occur in 2016.0.

Now if load your sheet into 2016 the errors occur as executed.  So it is something with you're entering and deleting on the sheet as it can not be duplicated unless someone with 2016.1 update can confirm.

And this is just bad programming executionon your part...

plot(t,x=0..2)

what you mean to do is plot(x,x=0..2) or plot(t,t=0..2)

add(i,i=[op(sn)])

but this adds all of them so a little modification

ps:=proc(a,b)
  add(i,i=[op(a)[1..b]])
end proc:

proc(sn,3)

  a1+a2+a3

So as Markiyan pointed to Acers solution, yours could look like this

plot(sin((1/180)*Pi*x), x = -180 .. 180, tickmarks = [[seq(180*i*(1/4) = (180*i*(1/4))*`°`, i = -4 .. 4)], default])

Couldn't you just put it in the quotes?

plot(sin((1/180)*Pi*x), x = -180 .. 180, axis[1] = [tickmarks = [90 = typeset("90°")]])

@mapleatha 

You could try

printf("The Equation Is: %a",EQ)