Opening MuseScore 1 Files in Musescore 2

Welcome aboard!
Would you to attach here your score? Someone could have a look.
Click File attachments, down under the frame of the post.

The message mean just waht they say: the file is corrupted, and has the problems that are described. Basically, measure that contain too many or too few beats according to the time signature and/or whatever deliberate changes you might have previous made in measure properties. You can see the problems just as clearly in 1.3; it just didn't bother to tell you about them. For instance, the first problem it tells you about is measure 12 (starting from 0, so measure 13 the way you or I would count). Staff 7 counting from the top is the second clarinet part. Count the beats in that measure - see the problem? Try deleting notes, or enetering new ones, and the problem just gets worse. A bug in 1.3 allowed this to happen, and 1.3 wasn't smart to detect it. 2.0 detects the problem so you can try to fix it.

Unfortunately, that's often easier said than done. Best course is sometimes to just compeltely remove (Ctrl+Delete) the problem measures, insert new ones, and reenter the music.

See How to fix a score that opens with the warning "File corrupted" . There's also a discussion at Can anyone tell me what this means and what I can do to fix it? .

Wow! Lots of similar errors, so instead of deleting/rewriting try this:
1. For all the Staff 7 and Staff 8 which read 'Expected: 4/4; Found: 28/16' --> These are the majority of the errors.
Do this:
a) To start, select Measure 12 on both staff 7 and staff 8 by shift clicking so both measures are highlighted.
b) Use menu item Edit to Exchange Voice 1-2 then hit Esc (to unselect the measures).
c) Ctrl click to select the two rests in voice 2 (one on staff 7, the other on staff 8 - they turn green when selected), and delete them. (You may have to zoom in.)
d) Select both measures again and swap the voices back
e) Hit Esc (to unselect the measures), and then delete the rests in the second (green) voice.
Repeat the above for measures 14, 16, 18, 142, 144, 146, 148.

2. For the measures that say: 'Expected: 4/4; Found: 3/4 (excluding measure 170)
Do this:
These measures have only rests, so click on the first rest and change the duration to a whole note rest.
Then, to change the whole note rest into a whole measure rest (so the rest gets centered in the measure like the other staves) simply select the measure (not the rest) and hit 'Delete'. --- *NOT* Ctrl Del.

3. For measure 17 Staff 7 and measure 147 Staff 7
Do this:
a) select the quarter rest and press '6' - then '.' (a dot) - then '5'.

4. The remaining measures have notes which may have to be re-entered as it's difficult to tell on what beat the rest should fall, or if note(s) are missing.

Regards.